KCET PYQ CHEMISTRY 12-1-1

🥳 Wohoo! Correct answer

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💡 Key Formula

None required

📚 Problem Solving Strategy

Define colligative properties: depend on number of particles

Check each option against definition

Identify optical activity depends on structure not concentration

⚠️ Common Mistakes

Confusing intensive and colligative properties

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Look for property that depends on molecular structure

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💡 Key Formula

None required

📚 Problem Solving Strategy

Define colligative properties: depend on number of particles

Check each option against definition

Identify optical activity depends on structure not concentration

⚠️ Common Mistakes

Confusing intensive and colligative properties

After adding a non-volatile solute, freezing point decreases to -0.186°C. Calculate ΔT.

0.521

0.0521

1.86

0.0186

🥳 Wohoo! Correct answer

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💡 Key Formula

ΔT = i x Kf x m.

📚 Problem Solving Strategy

Apply colligative property: ΔT = iKfm.

ΔT = (0.1) x (0.521 K kg/mol) = 0.0521.

Freezing point depression is directly proportional to solute molality.

⚠️ Common Mistakes

Incorrectly calculating colligative properties due to formula errors.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Carefully calculate using Van’t Hoff factor and molality.

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💡 Key Formula

ΔT = i x Kf x m.

📚 Problem Solving Strategy

Apply colligative property: ΔT = iKfm.

ΔT = (0.1) x (0.521 K kg/mol) = 0.0521.

Freezing point depression is directly proportional to solute molality.

⚠️ Common Mistakes

Incorrectly calculating colligative properties due to formula errors.

100 cm³ of 1M CH₃COOH was mixed with 100 cm³ of 2M CH₃OH to form an ester. The change in the initial rate if each solution is diluted with an equal volume of water would be

2 times

4 times

0.5 times

0.25 times

🥳 Wohoo! Correct answer

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💡 Key Formula

Rate = k × [CH₃COOH] × [CH₃OH].

📚 Problem Solving Strategy

Rate = k × [CH₃COOH] × [CH₃OH]. Dilution halves concentrations, reducing the rate by a factor of 1/4.

Rate reduction = (1/2 × 1/2) = 1/4 (0.25 times the original rate).

Final result: Rate decreases to 0.25 times.

⚠️ Common Mistakes

Miscalculating rate reduction factor.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Relate rate changes to dilution effect on reactant concentrations.

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💡 Key Formula

Rate = k × [CH₃COOH] × [CH₃OH].

📚 Problem Solving Strategy

Rate = k × [CH₃COOH] × [CH₃OH]. Dilution halves concentrations, reducing the rate by a factor of 1/4.

Rate reduction = (1/2 × 1/2) = 1/4 (0.25 times the original rate).

Final result: Rate decreases to 0.25 times.

⚠️ Common Mistakes

Miscalculating rate reduction factor.

How many Coulombs of electricity are required for the oxidation of one mole of water to dioxygen?

9.65 × 10³ C

1.93 × 10⁴ C

1.93 × 10⁵ C

19.3 × 10⁴ C

🥳 Wohoo! Correct answer

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💡 Key Formula

4 moles of electrons → 1 mole O₂: 4 × 96,500 C.

📚 Problem Solving Strategy

Reaction: H₂O → O₂ + 4H⁺ + 4e⁻. Each mole of O₂ requires 4 moles of electrons.

Charge = 4 × Faraday constant (96,500 C) = 1.93 × 10⁵ C.

Final result: Charge required = 1.93 × 10⁵ C.

⚠️ Common Mistakes

Miscalculating charge by ignoring Faraday's laws.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Relate oxidation to Faraday’s laws of electrolysis.

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💡 Key Formula

4 moles of electrons → 1 mole O₂: 4 × 96,500 C.

📚 Problem Solving Strategy

Reaction: H₂O → O₂ + 4H⁺ + 4e⁻. Each mole of O₂ requires 4 moles of electrons.

Charge = 4 × Faraday constant (96,500 C) = 1.93 × 10⁵ C.

Final result: Charge required = 1.93 × 10⁵ C.

⚠️ Common Mistakes

Miscalculating charge by ignoring Faraday's laws.

Half-life period of a first-order reaction is 10 min. Starting with initial concentration of 12 M, the rate after 20 min is

0.0693 M/min

0.693 × 3 M/min

0.0693 × 3 M/min

0.0693 × 4 M/min

🥳 Wohoo! Correct answer

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💡 Key Formula

Rate = k × [A], k = 0.693/t₁/₂.

📚 Problem Solving Strategy

Use first-order kinetics: k = 0.693/t₁/₂.

Rate = k × [A]. Substituting k = 0.693/10 and [A] = 3 M (half of initial).

Final result: Rate = 0.0693 × 3 M/min.

⚠️ Common Mistakes

Miscalculating k or using incorrect half-life formula.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Use first-order reaction rate equation and calculate time elapsed.

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💡 Key Formula

Rate = k × [A], k = 0.693/t₁/₂.

📚 Problem Solving Strategy

Use first-order kinetics: k = 0.693/t₁/₂.

Rate = k × [A]. Substituting k = 0.693/10 and [A] = 3 M (half of initial).

Final result: Rate = 0.0693 × 3 M/min.

⚠️ Common Mistakes

Miscalculating k or using incorrect half-life formula.

Which aqueous solution has the highest freezing point?

0.1 M Sucrose

0.01 M NaCl

0.1 M NaCl

0.01 M Na₂SO₄

🥳 Wohoo! Correct answer

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💡 Key Formula

ΔTf = i x Kf x m.

📚 Problem Solving Strategy

Freezing point depression depends on molality (m) and van’t Hoff factor (i).

i (Sucrose) = 1, i (NaCl) = 2, i (Na₂SO₄) = 3. Freezing point decreases with i.

Final result: Solution with 0.01 M NaCl has the highest freezing point.

⚠️ Common Mistakes

Confusing freezing point depression with molarity alone.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Relate freezing point depression to van’t Hoff factor and molality.

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💡 Key Formula

ΔTf = i x Kf x m.

📚 Problem Solving Strategy

Freezing point depression depends on molality (m) and van’t Hoff factor (i).

i (Sucrose) = 1, i (NaCl) = 2, i (Na₂SO₄) = 3. Freezing point decreases with i.

Final result: Solution with 0.01 M NaCl has the highest freezing point.

⚠️ Common Mistakes

Confusing freezing point depression with molarity alone.

In a first-order reaction, the concentration of the reactant is reduced to 12.5% in one hour. When was it half completed?

3 hr

20 min

30 min

15 min

🥳 Wohoo! Correct answer

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💡 Key Formula

t_half = 60 min / 3 = 20 min.

📚 Problem Solving Strategy

For a first-order reaction, 12.5% = (1/8) of the original concentration, meaning 3 half-lives.

Given total time = 60 min, divide it into 3 half-lives: t_half = 60 min / 3 = 20 min.

Final result: Half-life of reaction = 20 min.

⚠️ Common Mistakes

Misinterpreting reaction order or fraction left after given time.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Relate half-life and fraction of reactant remaining for first-order kinetics.

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💡 Key Formula

t_half = 60 min / 3 = 20 min.

📚 Problem Solving Strategy

For a first-order reaction, 12.5% = (1/8) of the original concentration, meaning 3 half-lives.

Given total time = 60 min, divide it into 3 half-lives: t_half = 60 min / 3 = 20 min.

Final result: Half-life of reaction = 20 min.

⚠️ Common Mistakes

Misinterpreting reaction order or fraction left after given time.

For a chemical reaction, mA → xB, the rate law is r = k[A]². If the concentration of A is doubled, the reaction rate will be

Doubled

Quadrupled

Increases by 8 times

Unchanged

🥳 Wohoo! Correct answer

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💡 Key Formula

Rate = k[reactant]^order

📚 Problem Solving Strategy

Write rate equation r = k[A]²

Replace [A] with 2[A]

Simplify to get r = 4k[A]²

⚠️ Common Mistakes

Forgetting to square the factor

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Consider exponent in rate law

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💡 Key Formula

Rate = k[reactant]^order

📚 Problem Solving Strategy

Write rate equation r = k[A]²

Replace [A] with 2[A]

Simplify to get r = 4k[A]²

⚠️ Common Mistakes

Forgetting to square the factor

0.06% (w/v) aqueous solution of urea is isotonic with...

0.06% glucose

0.6% glucose

0.01 M glucose

0.1 M glucose

🥳 Wohoo! Correct answer

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💡 Key Formula

Molality = moles/volume; Isotonic solutions: Same molarity.

📚 Problem Solving Strategy

Isotonic solutions: Same molarity, moles of solute.

Calculate molality: (0.06/60) = 0.001 mol; isotonic with 0.01 M glucose.

Final result: Isotonic with 0.01 M glucose.

⚠️ Common Mistakes

Misinterpreting isotonicity due to incorrect molality calculation.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Carefully compare molarity and isotonic conditions.

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💡 Key Formula

Molality = moles/volume; Isotonic solutions: Same molarity.

📚 Problem Solving Strategy

Isotonic solutions: Same molarity, moles of solute.

Calculate molality: (0.06/60) = 0.001 mol; isotonic with 0.01 M glucose.

Final result: Isotonic with 0.01 M glucose.

⚠️ Common Mistakes

Misinterpreting isotonicity due to incorrect molality calculation.

The activation energy of a chemical reaction can be determined by

evaluating rate constants at two different temperatures

changing the concentration of reactants

evaluating the concentration of reactants at two different temperatures

evaluating rate constant at standard temperature

🥳 Wohoo! Correct answer

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💡 Key Formula

k = Ae^(-Ea/RT)

📚 Problem Solving Strategy

Write Arrhenius equation

Use equation at two temperatures

Take ratio to solve for Ea

⚠️ Common Mistakes

Confusing with collision theory

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Use rate constants at different temperatures

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💡 Key Formula

k = Ae^(-Ea/RT)

📚 Problem Solving Strategy

Write Arrhenius equation

Use equation at two temperatures

Take ratio to solve for Ea

⚠️ Common Mistakes

Confusing with collision theory

3A → 2B rate of reaction + d[B]/dt is equal to

(-3/2)(d[A]/dt)

(-2/3)(d[A]/dt)

(+2)(d[A]/dt)

(-1/3)(d[A]/dt)

🥳 Wohoo! Correct answer

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💡 Key Formula

Rate = -(coefficient of product/coefficient of reactant)(d[reactant]/dt)

📚 Problem Solving Strategy

Write balanced equation

Use stoichiometric relationship between A and B

Apply rate relation d[B]/dt = -(2/3)(d[A]/dt)

⚠️ Common Mistakes

Not accounting for stoichiometry

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Consider stoichiometric coefficients

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💡 Key Formula

Rate = -(coefficient of product/coefficient of reactant)(d[reactant]/dt)

📚 Problem Solving Strategy

Write balanced equation

Use stoichiometric relationship between A and B

Apply rate relation d[B]/dt = -(2/3)(d[A]/dt)

⚠️ Common Mistakes

Not accounting for stoichiometry

The amount of current in Faraday is required for the reduction of 1 mol of Cr₂O₇²⁻ ions to Cr³⁺ is

🥳 Wohoo! Correct answer

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💡 Key Formula

1F = 96,500 coulombs

📚 Problem Solving Strategy

Write balanced reduction equation

Calculate oxidation state change

Multiply by number of chromium atoms

⚠️ Common Mistakes

Not considering all Cr atoms

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Count electrons in half-reaction

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💡 Key Formula

1F = 96,500 coulombs

📚 Problem Solving Strategy

Write balanced reduction equation

Calculate oxidation state change

Multiply by number of chromium atoms

⚠️ Common Mistakes

Not considering all Cr atoms

Osmotic pressure of the solution can be increased by

increasing the temperature of the solution

decreasing the temperature of the solution

increasing the volume of the vessel

diluting the solution

🥳 Wohoo! Correct answer

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💡 Key Formula

π = CRT

📚 Problem Solving Strategy

Write van't Hoff equation π = CRT

Identify variables affecting π

Analyze direct relationship with T

⚠️ Common Mistakes

Confusing concentration effects

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Look at variables in osmotic pressure equation

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💡 Key Formula

π = CRT

📚 Problem Solving Strategy

Write van't Hoff equation π = CRT

Identify variables affecting π

Analyze direct relationship with T

⚠️ Common Mistakes

Confusing concentration effects

Which of the following is incorrect in a galvanic cell?

Oxidation occurs at anode

Reduction occurs at cathode

The electrode at which electrons are gained is called the cathode

The electrode at which electrons are lost is called the cathode

🥳 Wohoo! Correct answer

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💡 Key Formula

Anode: oxidation (-e⁻)
Cathode: reduction (+e⁻)

📚 Problem Solving Strategy

List correct galvanic cell principles

Identify cathode gains electrons

Note anode loses electrons

⚠️ Common Mistakes

Confusing anode and cathode processes

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Remember ANODE = OX, CATHODE = RED

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💡 Key Formula

Anode: oxidation (-e⁻)
Cathode: reduction (+e⁻)

📚 Problem Solving Strategy

List correct galvanic cell principles

Identify cathode gains electrons

Note anode loses electrons

⚠️ Common Mistakes

Confusing anode and cathode processes

A secondary cell is one

can be recharged

can be recharged by passing a current through it in the same direction

can be recharged by passing a current through it in the opposite direction

cannot be recharged

🥳 Wohoo! Correct answer

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💡 Key Formula

None required

📚 Problem Solving Strategy

Define secondary cell

Understand recharging reverses reactions

Identify current direction must oppose discharge

⚠️ Common Mistakes

Confusion about current direction

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Think about reaction reversal

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💡 Key Formula

None required

📚 Problem Solving Strategy

Define secondary cell

Understand recharging reverses reactions

Identify current direction must oppose discharge

⚠️ Common Mistakes

Confusion about current direction

The half-life period of a 1st order reaction is 60 minutes. What percentage will be left over after 240 minutes?

6.25%

1.25%

🥳 Wohoo! Correct answer

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💡 Key Formula

• t₁/₂ = (2.303/k)log 2
• k = [2.303/60]log 2
• t = (2.303/k)log(a/[a-x])

📚 Problem Solving Strategy

Calculate k using half-life equation: t₁/₂ = (2.303/k)log 2

Substitute t=240 min and solve: log(a/[a-x]) = 4log 2

Calculate remaining percentage: [a-x] = 100/16 = 6.25%

⚠️ Common Mistakes

Students often forget to convert final concentration to percentage

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Use half-life to find k first, then use it in time equation

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💡 Key Formula

• t₁/₂ = (2.303/k)log 2
• k = [2.303/60]log 2
• t = (2.303/k)log(a/[a-x])

📚 Problem Solving Strategy

Calculate k using half-life equation: t₁/₂ = (2.303/k)log 2

Substitute t=240 min and solve: log(a/[a-x]) = 4log 2

Calculate remaining percentage: [a-x] = 100/16 = 6.25%

⚠️ Common Mistakes

Students often forget to convert final concentration to percentage

Which statement is incorrect?

Rate law cannot be determined experimentally

Complex reactions have fractional order

Bimolecular reactions involve simultaneous collision

Molecularity only for elementary reaction

🥳 Wohoo! Correct answer

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💡 Key Formula

Rate = k[A]ˣ[B]ʸ

📚 Problem Solving Strategy

Check rate law determination

Consider experimental methods

Identify false statement

⚠️ Common Mistakes

Rate law confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Rate law can be determined

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💡 Key Formula

Rate = k[A]ˣ[B]ʸ

📚 Problem Solving Strategy

Check rate law determination

Consider experimental methods

Identify false statement

⚠️ Common Mistakes

Rate law confusion

Which aqueous solution has highest freezing point?

0.1 molal Al₂(SO₄)₃

0.1 molal BaCl₂

0.1 molal AlCl₃

0.1 molal NH₄Cl

🥳 Wohoo! Correct answer

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💡 Key Formula

ΔTf = Kf × m × i

📚 Problem Solving Strategy

Calculate i-factor for each

Compare number of ions

NH₄Cl has lowest i

⚠️ Common Mistakes

i-factor calculation

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Less ions = higher FP

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💡 Key Formula

ΔTf = Kf × m × i

📚 Problem Solving Strategy

Calculate i-factor for each

Compare number of ions

NH₄Cl has lowest i

⚠️ Common Mistakes

i-factor calculation

Hydrogenation of vegetable oils in presence of finely divided nickel as catalyst is

Heterogeneous catalysis

Homogeneous catalysis

Enzyme catalysed

Liquid catalysed

🥳 Wohoo! Correct answer

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💡 Key Formula

Oil(l) + H₂(g) -[Ni(s)]→

📚 Problem Solving Strategy

Check phase of reactants

Check phase of catalyst

Compare phases

⚠️ Common Mistakes

Catalyst phase confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Different phases = heterogeneous

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💡 Key Formula

Oil(l) + H₂(g) -[Ni(s)]→

📚 Problem Solving Strategy

Check phase of reactants

Check phase of catalyst

Compare phases

⚠️ Common Mistakes

Catalyst phase confusion

For reaction (1/2)A → 2B, rate of disappearance of A related to rate of appearance of B by

-d[A]/dt = 4[d[B]/dt]

-d[A]/dt = (1/4)[d[B]/dt]

-d[A]/dt = (1/2)[d[B]/dt]

-d[A]/dt = [d[B]/dt]

🥳 Wohoo! Correct answer

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💡 Key Formula

Rate₍A₎:Rate₍B₎ = 1:4

📚 Problem Solving Strategy

Write balanced equation

Compare coefficients

Use stoichiometry

⚠️ Common Mistakes

Stoichiometric ratio

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Consider stoichiometric ratio

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💡 Key Formula

Rate₍A₎:Rate₍B₎ = 1:4

📚 Problem Solving Strategy

Write balanced equation

Compare coefficients

Use stoichiometry

⚠️ Common Mistakes

Stoichiometric ratio

In electrolysis of NaCl(aq), anode half cell reaction is

Na⁺ + e⁻ → Na

2H₂O → O₂ + 4H⁺ + 4e⁻

H⁺ + e⁻ → ½H₂

Cl⁻ → ½Cl₂ + e⁻

🥳 Wohoo! Correct answer

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💡 Key Formula

2Cl⁻ → Cl₂ + 2e⁻

📚 Problem Solving Strategy

Compare E° values

Consider conditions

Identify anode reaction

⚠️ Common Mistakes

Half-cell identification

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Oxidation at anode

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💡 Key Formula

2Cl⁻ → Cl₂ + 2e⁻

📚 Problem Solving Strategy

Compare E° values

Consider conditions

Identify anode reaction

⚠️ Common Mistakes

Half-cell identification

Given half cell reactions with E°: Strongest reducing agent?

Zn(s)

Cr(s)

H₂(g)

F₂(g)

🥳 Wohoo! Correct answer

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💡 Key Formula

E°(Zn²⁺/Zn) = -0.76V

📚 Problem Solving Strategy

Compare E° values

Most negative = strongest

Zn has -0.76V

⚠️ Common Mistakes

Potential comparison

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Check reduction potentials

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💡 Key Formula

E°(Zn²⁺/Zn) = -0.76V

📚 Problem Solving Strategy

Compare E° values

Most negative = strongest

Zn has -0.76V

⚠️ Common Mistakes

Potential comparison

NaClO₃ converts to NaClO₄, how many moles formed with 3F charge?

0.75

1.5

🥳 Wohoo! Correct answer

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💡 Key Formula

n = Q/nF

📚 Problem Solving Strategy

Write balanced equation

Calculate e⁻ needed

Use Faraday relation

⚠️ Common Mistakes

Faraday calculation

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

2e⁻ per molecule

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💡 Key Formula

n = Q/nF

📚 Problem Solving Strategy

Write balanced equation

Calculate e⁻ needed

Use Faraday relation

⚠️ Common Mistakes

Faraday calculation

The Vant Hoff's factor 'i' accounts for

Extent of solubility

Extent of dissociation

Extent of dissolution

Extent of mobility

🥳 Wohoo! Correct answer

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💡 Key Formula

i = actual/normal

📚 Problem Solving Strategy

Consider solution behavior

Check ionic dissociation

Relate to colligative

⚠️ Common Mistakes

Factor interpretation

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

i measures dissociation

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💡 Key Formula

i = actual/normal

📚 Problem Solving Strategy

Consider solution behavior

Check ionic dissociation

Relate to colligative

⚠️ Common Mistakes

Factor interpretation

When pure solvent diffuses out through semipermeable membrane, process is

Osmosis

Reverse osmosis

Sorption

Dialysis

🥳 Wohoo! Correct answer

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💡 Key Formula

ΔP > π (for RO)

📚 Problem Solving Strategy

Consider direction

Check pressure

Identify process

⚠️ Common Mistakes

Process direction

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Solvent out = RO

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💡 Key Formula

ΔP > π (for RO)

📚 Problem Solving Strategy

Consider direction

Check pressure

Identify process

⚠️ Common Mistakes

Process direction

The value of rate constant of a pseudo-first-order reaction

Depends only on temperature

Depends on concentration of reactants present in small amounts

Depends on concentration of reactants present in excess

Is independent of concentration

🥳 Wohoo! Correct answer

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💡 Key Formula

Rate = k[A], k includes [B]excess

📚 Problem Solving Strategy

Understand pseudo order

Check concentration effects

Evaluate rate law

⚠️ Common Mistakes

Students confuse true and pseudo orders

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Excess reactant concentration

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💡 Key Formula

Rate = k[A], k includes [B]excess

📚 Problem Solving Strategy

Understand pseudo order

Check concentration effects

Evaluate rate law

⚠️ Common Mistakes

Students confuse true and pseudo orders

For a cell reaction involving two-electron changes, E°cell = 0.3 V at 25°C. The equilibrium constant of the reaction is

10⁻¹⁰

3 × 10⁻²

10¹⁰

🥳 Wohoo! Correct answer

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💡 Key Formula

K = exp(-nFE°/RT)

📚 Problem Solving Strategy

Use Nernst equation

Apply electron number

Calculate K

⚠️ Common Mistakes

Students forget temperature factor

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

ΔG° = -nFE° = -RTlnK

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💡 Key Formula

K = exp(-nFE°/RT)

📚 Problem Solving Strategy

Use Nernst equation

Apply electron number

Calculate K

⚠️ Common Mistakes

Students forget temperature factor

Which of the following is not a conductor of electricity?

Solid NaCl

Fused NaCl

Brine solution

🥳 Wohoo! Correct answer

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💡 Key Formula

Conductivity needs mobile charges

📚 Problem Solving Strategy

Check ion mobility

Consider electron flow

Evaluate conductivity

⚠️ Common Mistakes

Students forget ion mobility requirement

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Ions must be mobile

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💡 Key Formula

Conductivity needs mobile charges

📚 Problem Solving Strategy

Check ion mobility

Consider electron flow

Evaluate conductivity

⚠️ Common Mistakes

Students forget ion mobility requirement

The temperature coefficient of a reaction is 2. When the temperature is increased from 30°C to 90°C, the rate of reaction is increased by

150 times

410 times

72 times

64 times

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Rate = 2^(ΔT/10)

📚 Problem Solving Strategy

Calculate temperature difference

Apply rate rule

Use coefficient value

⚠️ Common Mistakes

Students forget to divide temperature difference by 10

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Rate doubles every 10°C

This is some text inside of a div block.

💡 Key Formula

Rate = 2^(ΔT/10)

📚 Problem Solving Strategy

Calculate temperature difference

Apply rate rule

Use coefficient value

⚠️ Common Mistakes

Students forget to divide temperature difference by 10

Isotonic solutions are solutions having the same

Surface tension

Vapour pressure

Osmotic pressure

Viscosity

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

π = MRT

📚 Problem Solving Strategy

Compare colligative properties

Understand osmosis

Check concentration effect

⚠️ Common Mistakes

Students confuse different colligative properties

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Equal solute concentration

This is some text inside of a div block.

💡 Key Formula

π = MRT

📚 Problem Solving Strategy

Compare colligative properties

Understand osmosis

Check concentration effect

⚠️ Common Mistakes

Students confuse different colligative properties

Plot of t₁/₂ vs [R]₀ for a reaction is straight line parallel to x-axis. Unit for rate constant is

mol L⁻¹s

mol L⁻¹ s⁻¹

L mol⁻¹ s⁻¹

s⁻¹

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

k = 0.693/t₁/₂

📚 Problem Solving Strategy

Identify order from graph

Check t₁/₂ formula for first-order

Determine k units

⚠️ Common Mistakes

Not relating t₁/₂ to reaction order

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Constant t₁/₂ indicates first order

This is some text inside of a div block.

💡 Key Formula

k = 0.693/t₁/₂

📚 Problem Solving Strategy

Identify order from graph

Check t₁/₂ formula for first-order

Determine k units

⚠️ Common Mistakes

Not relating t₁/₂ to reaction order

At a particular temperature, the ratio of molar conductance to specific conductance of 0.01 M NaCl solution is

10⁵ cm³ mol⁻¹

10³ cm³ mol⁻¹

10 cm³ mol⁻¹

10⁵ cm² mol⁻¹

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Λm = κ × (1000/c)

📚 Problem Solving Strategy

Use conductance relation

Apply concentration

Calculate ratio

⚠️ Common Mistakes

Confusion between molar and specific conductance

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Λm = κ/c

This is some text inside of a div block.

💡 Key Formula

Λm = κ × (1000/c)

📚 Problem Solving Strategy

Use conductance relation

Apply concentration

Calculate ratio

⚠️ Common Mistakes

Confusion between molar and specific conductance

Electrolytic refining is used to purify which of the following metals?

Cu and Zn

Ge and Si

Zr and Ti

Zn and Hg

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Anode: M → M²⁺ + 2e⁻
Cathode: M²⁺ + 2e⁻ → M

📚 Problem Solving Strategy

Consider electrode potential

Check metal reactivity

Evaluate purification method

⚠️ Common Mistakes

Students confuse electrolytic and pyrometallurgical refining

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Look for commonly refined metals

This is some text inside of a div block.

💡 Key Formula

Anode: M → M²⁺ + 2e⁻
Cathode: M²⁺ + 2e⁻ → M

📚 Problem Solving Strategy

Consider electrode potential

Check metal reactivity

Evaluate purification method

⚠️ Common Mistakes

Students confuse electrolytic and pyrometallurgical refining

For the reaction, 2SO₂ + O₂ ⇌ 2SO₃, The rate of disappearance of O₂ is 2 × 10⁻⁴ mol L⁻¹ s⁻¹. The rate of appearance of SO₃ is

2 × 10⁻⁴ mol L⁻¹ s⁻¹

4 × 10⁻⁴ mol L⁻¹ s⁻¹

1 × 10⁻¹ mol L⁻¹ s⁻¹

6 × 10⁻⁴ mol L⁻¹ s⁻¹

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Rate ratios = stoichiometric ratios

📚 Problem Solving Strategy

Write balanced equation

Apply stoichiometric ratio

Calculate relative rates

⚠️ Common Mistakes

Students ignore stoichiometric coefficients

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Consider coefficients

This is some text inside of a div block.

💡 Key Formula

Rate ratios = stoichiometric ratios

📚 Problem Solving Strategy

Write balanced equation

Apply stoichiometric ratio

Calculate relative rates

⚠️ Common Mistakes

Students ignore stoichiometric coefficients

Which of the following aqueous solutions should have the highest boiling point?

1.0 M NaOH

1.0 M Na₂SO₄

1.0 M NH₄NO₃

1.0 M KNO₃

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

ΔTb = iKbm

📚 Problem Solving Strategy

Count total ions

Calculate van't Hoff factor

Compare colligative properties

⚠️ Common Mistakes

Students forget to count total ions

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

More ions = higher boiling point

This is some text inside of a div block.

💡 Key Formula

ΔTb = iKbm

📚 Problem Solving Strategy

Count total ions

Calculate van't Hoff factor

Compare colligative properties

⚠️ Common Mistakes

Students forget to count total ions

The charge required for the reduction of 1 mole of MnO₄⁻ to MnO₂ is

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Q = nFe⁻

📚 Problem Solving Strategy

Calculate oxidation states

Find electron change

Apply Faraday's law

⚠️ Common Mistakes

Confusion in oxidation state changes

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Count electrons transferred

This is some text inside of a div block.

💡 Key Formula

Q = nFe⁻

📚 Problem Solving Strategy

Calculate oxidation states

Find electron change

Apply Faraday's law

⚠️ Common Mistakes

Confusion in oxidation state changes

Solution A (acetone in chloroform) and B (acetone in CS₂) show which deviation from Raoult's law

positive and positive

positive and negative

negative and negative

negative and positive

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Deviation ∝ interactions

📚 Problem Solving Strategy

Check solute-solvent interactions

Compare with pure component interactions

Determine deviation type

⚠️ Common Mistakes

Not considering molecular interactions

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Compare intermolecular forces

This is some text inside of a div block.

💡 Key Formula

Deviation ∝ interactions

📚 Problem Solving Strategy

Check solute-solvent interactions

Compare with pure component interactions

Determine deviation type

⚠️ Common Mistakes

Not considering molecular interactions

Non-volatile solute 'A' tetramerizes in water to 80%. 2.5g in 100g water lowers freezing point by 0.3°C. Molar mass of A₀ is (Kf=1.86)

221

155

354

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

ΔTf = Kf × m × i

📚 Problem Solving Strategy

Calculate effective particles

Apply freezing point depression

Consider tetramerization

⚠️ Common Mistakes

Not considering association

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Account for degree of association

This is some text inside of a div block.

💡 Key Formula

ΔTf = Kf × m × i

📚 Problem Solving Strategy

Calculate effective particles

Apply freezing point depression

Consider tetramerization

⚠️ Common Mistakes

Not considering association

Given: E°(Mn²⁺/Mn)=1.5V and E°(Mn⁴⁺/Mn²⁺)=1.2V, then E°(Mn⁴⁺/Mn) is

0.3V

0.1V

1.7V

2.1V

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

E°total = E°₁ + E°₂

📚 Problem Solving Strategy

Write half-cell reactions

Apply E°cell = E°red + E°oxd

Sum potentials correctly

⚠️ Common Mistakes

Not adding potentials correctly

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Use relationship between reduction potentials

This is some text inside of a div block.

💡 Key Formula

E°total = E°₁ + E°₂

📚 Problem Solving Strategy

Write half-cell reactions

Apply E°cell = E°red + E°oxd

Sum potentials correctly

⚠️ Common Mistakes

Not adding potentials correctly

An aqueous solution of CuSO₄ is subjected to electrolysis using inert electrodes. The pH will

increase

remains unchanged

decrease

depends on current

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

2H₂O → O₂ + 4H⁺ + 4e⁻

📚 Problem Solving Strategy

Write anode reaction: 2H₂O → O₂ + 4H⁺

Write cathode reaction: Cu²⁺ + 2e⁻ → Cu

Net increase in H⁺ concentration

⚠️ Common Mistakes

Not considering water electrolysis

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Look for H⁺ production

This is some text inside of a div block.

💡 Key Formula

2H₂O → O₂ + 4H⁺ + 4e⁻

📚 Problem Solving Strategy

Write anode reaction: 2H₂O → O₂ + 4H⁺

Write cathode reaction: Cu²⁺ + 2e⁻ → Cu

Net increase in H⁺ concentration

⚠️ Common Mistakes

Not considering water electrolysis

One litre solution of MgCl₂ electrolyzed by passing 1A current for 16min 5sec. Original concentration was (Mg=24)

5×10⁻³ M

5×10⁻² M

0.5×10⁻³ M

1.0×10⁻² M

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

It = nFM

📚 Problem Solving Strategy

Calculate time in seconds: 965s

Apply Faraday's law: m = (It×M)/(nF)

Convert mass to molarity

⚠️ Common Mistakes

Forgetting to convert time to seconds

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Use Faraday's equation

This is some text inside of a div block.

💡 Key Formula

It = nFM

📚 Problem Solving Strategy

Calculate time in seconds: 965s

Apply Faraday's law: m = (It×M)/(nF)

Convert mass to molarity

⚠️ Common Mistakes

Forgetting to convert time to seconds

Relative lowering of vapor pressure of a dilute solution of glucose in 1 kg water is 0.002. The molality is

0.004

0.222

0.111

0.021

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

(P₀-P)/P₀ = n₂/(n₁+n₂)

📚 Problem Solving Strategy

Apply Raoult's law: (P₀-P)/P₀ = xₛ

Convert to molality using relative pressure

molality = 0.002/0.018 = 0.111

⚠️ Common Mistakes

Not converting mole fraction to molality

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Use relation between molality and vapor pressure

This is some text inside of a div block.

💡 Key Formula

(P₀-P)/P₀ = n₂/(n₁+n₂)

📚 Problem Solving Strategy

Apply Raoult's law: (P₀-P)/P₀ = xₛ

Convert to molality using relative pressure

molality = 0.002/0.018 = 0.111

⚠️ Common Mistakes

Not converting mole fraction to molality

Which is an example of homogeneous catalysis?

oxidation of NH₃ in Ostwald's process

oxidation of SO₂ in contact process

oxidation of SO₂ in lead chamber process

manufacture of NH₃ by Haber's process

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

SO₂ + NO₂ → SO₃ (all gases)

📚 Problem Solving Strategy

Check phase of catalyst

Verify reactant phase

Confirm homogeneity

⚠️ Common Mistakes

Not checking phase of catalyst

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Catalyst and reactants in same phase

This is some text inside of a div block.

💡 Key Formula

SO₂ + NO₂ → SO₃ (all gases)

📚 Problem Solving Strategy

Check phase of catalyst

Verify reactant phase

Confirm homogeneity

⚠️ Common Mistakes

Not checking phase of catalyst

1L of 2M CH₃COOH mixed with 1L of 3M C₂H₅OH, rate after dilution with equal volume of water will be

0.25 times

2 times

0.5 times

4 times

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Rate = k[acid][alcohol]

📚 Problem Solving Strategy

Calculate new concentrations

Apply rate equation

Compare rates

⚠️ Common Mistakes

Not considering concentration changes

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Rate ∝ [CH₃COOH][C₂H₅OH]

This is some text inside of a div block.

💡 Key Formula

Rate = k[acid][alcohol]

📚 Problem Solving Strategy

Calculate new concentrations

Apply rate equation

Compare rates

⚠️ Common Mistakes

Not considering concentration changes

The number of moles of electron required to reduce 0.2 mole of Cr₂O₇²⁻ to Cr³⁺

1.2

0.6

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Cr₂O₇²⁻ + 14H⁺ + 6e⁻ → 2Cr³⁺ + 7H₂O

📚 Problem Solving Strategy

Write half reaction

Balance electrons

Calculate moles needed

⚠️ Common Mistakes

Forgetting to account for stoichiometry

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Count electrons in reduction equation

This is some text inside of a div block.

💡 Key Formula

Cr₂O₇²⁻ + 14H⁺ + 6e⁻ → 2Cr³⁺ + 7H₂O

📚 Problem Solving Strategy

Write half reaction

Balance electrons

Calculate moles needed

⚠️ Common Mistakes

Forgetting to account for stoichiometry

Which is a wrong statement?

Rate constant k=A if Ea=0

e⁻ᴱᵃ/ᴿᵀ gives fraction of activated molecules

ln k vs 1/T plot is straight line

presence of catalyst will not alter Ea

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

k = Ae⁻ᴱᵃ/ᴿᵀ

📚 Problem Solving Strategy

Check Arrhenius equation

Verify catalyst effect

Compare statements

⚠️ Common Mistakes

Not understanding catalyst role

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Catalyst lowers activation energy

This is some text inside of a div block.

💡 Key Formula

k = Ae⁻ᴱᵃ/ᴿᵀ

📚 Problem Solving Strategy

Check Arrhenius equation

Verify catalyst effect

Compare statements

⚠️ Common Mistakes

Not understanding catalyst role

The rate constant of a reaction is given by k=PZe⁻Eₐ/RT under standard notation. To speed up the reaction, which factor should be decreased?

Both Z and T

Eₐ

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

k = PZe⁻Eₐ/RT

📚 Problem Solving Strategy

Analyze Arrhenius equation

Check temperature effect

Identify rate-limiting factor

⚠️ Common Mistakes

Arrhenius equation

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Lower activation energy increases rate

This is some text inside of a div block.

💡 Key Formula

k = PZe⁻Eₐ/RT

📚 Problem Solving Strategy

Analyze Arrhenius equation

Check temperature effect

Identify rate-limiting factor

⚠️ Common Mistakes

Arrhenius equation

The time required for 60% completion of a first order reaction is 50 min. The time required for 93.6% completion of the same reaction will be

100 min

83.8 min

50 min

150 min

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

None

📚 Problem Solving Strategy

Use first order equation

Calculate rate constant

Find t for 93.6%

⚠️ Common Mistakes

First order kinetics

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

k = (2.303/t)log[a₀/(a₀-x)]

This is some text inside of a div block.

💡 Key Formula

None

📚 Problem Solving Strategy

Use first order equation

Calculate rate constant

Find t for 93.6%

⚠️ Common Mistakes

First order kinetics

In which of the following cases a chemical reaction is possible?

ZnSO₄(aq) is placed in copper vessel

When AgNO₃ solution is stirred with copper spoon

Conc. HNO₃ is stored in platinum vessel

Gold ornaments are washed with dil HCl

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Ag⁺ + Cu → Cu²⁺ + Ag

📚 Problem Solving Strategy

Compare E° values

Check reactivity series

Identify possible reaction

⚠️ Common Mistakes

Metal reactivity

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Cu reduces Ag⁺

This is some text inside of a div block.

💡 Key Formula

Ag⁺ + Cu → Cu²⁺ + Ag

📚 Problem Solving Strategy

Compare E° values

Check reactivity series

Identify possible reaction

⚠️ Common Mistakes

Metal reactivity

For an elementary reaction 2A + 3B → 4C + D, when rate of appearance of C at time 't' is 2.8×10⁻³ mol L⁻¹S⁻¹, rate of disappearance of B at 't' will be

4/3(2.8×10⁻³)mol L⁻¹S⁻¹

3/4(2.8×10⁻³)mol L⁻¹S⁻¹

2(2.8×10⁻³)mol L⁻¹S⁻¹

1/4(2.8×10⁻³)mol L⁻¹S⁻¹

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

None

📚 Problem Solving Strategy

Write rate expression

Use stoichiometry

Calculate rate ratio

⚠️ Common Mistakes

Rate relationships

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

-rB/rC = 3/4

This is some text inside of a div block.

💡 Key Formula

None

📚 Problem Solving Strategy

Write rate expression

Use stoichiometry

Calculate rate ratio

⚠️ Common Mistakes

Rate relationships

When an aqueous solution of NaF is electrolyzed between inert electrodes, the product obtained at anode is

F₂

H₂

O₂

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

2H₂O → O₂ + 4H⁺ + 4e⁻

📚 Problem Solving Strategy

Check oxidation potentials

Compare E° values

Identify anode product

⚠️ Common Mistakes

Electrolysis products

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Water oxidizes before F⁻

This is some text inside of a div block.

💡 Key Formula

2H₂O → O₂ + 4H⁺ + 4e⁻

📚 Problem Solving Strategy

Check oxidation potentials

Compare E° values

Identify anode product

⚠️ Common Mistakes

Electrolysis products

Given E°Fe³⁺/Fe²⁺ = +0.76V and E°I₂/I⁻ = +0.55V, the equilibrium constant for the reaction taking place in galvanic cell consisting of above two electrodes is [2.303RT/F = 0.06]

1×10⁷

1×10⁹

3×10⁸

5×10¹²

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

ΔG° = -nFE° = -RTlnK

📚 Problem Solving Strategy

Calculate E°cell

Use Nernst equation

Find equilibrium constant

⚠️ Common Mistakes

Cell potential

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

logK = nE°/0.06

This is some text inside of a div block.

💡 Key Formula

ΔG° = -nFE° = -RTlnK

📚 Problem Solving Strategy

Calculate E°cell

Use Nernst equation

Find equilibrium constant

⚠️ Common Mistakes

Cell potential

When solute 'X' dimerises in water to the extent of 80%, if 2.5g of 'X' in 100g of water increases boiling point by 0.3°C, the molar mass of 'X' is [Kₒ=0.52K kg mol⁻¹]

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

ΔTb = Kb × m × i

📚 Problem Solving Strategy

Calculate i factor

Use ΔTb formula

Find molar mass

⚠️ Common Mistakes

Degree of association

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Consider dimerization

This is some text inside of a div block.

💡 Key Formula

ΔTb = Kb × m × i

📚 Problem Solving Strategy

Calculate i factor

Use ΔTb formula

Find molar mass

⚠️ Common Mistakes

Degree of association

Which of the following pair of solutions is isotonic?

0.01M BaCl₂ and 0.015M NaCl

0.001M Al₂(SO₄)₃ and 0.01M BaCl₂

0.001M CaCl₂ and 0.001M Al₂(SO₄)₃

0.01M BaCl₂ and 0.001M CaCl₂

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

i = 1 + α(n-1)

📚 Problem Solving Strategy

Calculate total ions

Compare concentrations

Check van't Hoff factor

⚠️ Common Mistakes

van't Hoff factor

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Equal number of particles

This is some text inside of a div block.

💡 Key Formula

i = 1 + α(n-1)

📚 Problem Solving Strategy

Calculate total ions

Compare concentrations

Check van't Hoff factor

⚠️ Common Mistakes

van't Hoff factor

The pair of electrolytes that possess same λ°m value in Debye-Hückel-Onsagar equation, λm = λ°m - A√C is

MgSO₄, NaSO₄

NH₄Cl, NaBr

NaBr, MgSO₄

NaCl, CaCl₂

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

λm = λ°m - A√C

📚 Problem Solving Strategy

Check ion mobility

Compare charge

Analyze conductance

⚠️ Common Mistakes

Conductance concepts

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Similar ion mobilities

This is some text inside of a div block.

💡 Key Formula

λm = λ°m - A√C

📚 Problem Solving Strategy

Check ion mobility

Compare charge

Analyze conductance

⚠️ Common Mistakes

Conductance concepts

If 3g of glucose (molar mass = 180g) is dissolved in 60g of water at 15°C, the osmotic pressure of the solution will be

6.57 atm

5.57 atm

0.34 atm

0.65 atm

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

π = (nRT)/V

📚 Problem Solving Strategy

Use π = MRT

Calculate concentration

Convert to appropriate units

⚠️ Common Mistakes

Unit conversion errors

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Remember temperature in Kelvin

This is some text inside of a div block.

💡 Key Formula

π = (nRT)/V

📚 Problem Solving Strategy

Use π = MRT

Calculate concentration

Convert to appropriate units

⚠️ Common Mistakes

Unit conversion errors

The rise in boiling point of a solution containing 1.8 g of glucose in 100g of solvent is 0.1°C. The molal elevation constant of the liquid is

2K kg/mol

10K kg/mol

0.1K kg/mol

1K kg/mol

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

ΔTb = Kb×(w×1000)/(M×W)

📚 Problem Solving Strategy

Use ΔTb = Kb×m×i

Calculate molality

Solve for Kb

⚠️ Common Mistakes

Forgetting to convert units

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Consider van't Hoff factor

This is some text inside of a div block.

💡 Key Formula

ΔTb = Kb×(w×1000)/(M×W)

📚 Problem Solving Strategy

Use ΔTb = Kb×m×i

Calculate molality

Solve for Kb

⚠️ Common Mistakes

Forgetting to convert units

Solubility of a gas in a liquid increases with

increase of P and decrease of T

decrease of P and decrease of T

increase of P and increase of T

decrease of P and increase of T

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Henry's law: C = KP

📚 Problem Solving Strategy

Apply Henry's law

Consider Le Chatelier's principle

Temperature effect on solubility

⚠️ Common Mistakes

Confusing temperature effects

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Pressure directly proportional to solubility

This is some text inside of a div block.

💡 Key Formula

Henry's law: C = KP

📚 Problem Solving Strategy

Apply Henry's law

Consider Le Chatelier's principle

Temperature effect on solubility

⚠️ Common Mistakes

Confusing temperature effects

The molar conductivity is maximum for the solution of concentration

0.005 M

0.001 M

0.004 M

0.002 M

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Λₘ = κ×1000/M

📚 Problem Solving Strategy

Compare concentrations

Recall Λₘ vs concentration

Lowest concentration has highest Λₘ

⚠️ Common Mistakes

Forgetting inverse relationship

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Λₘ increases with dilution

This is some text inside of a div block.

💡 Key Formula

Λₘ = κ×1000/M

📚 Problem Solving Strategy

Compare concentrations

Recall Λₘ vs concentration

Lowest concentration has highest Λₘ

⚠️ Common Mistakes

Forgetting inverse relationship

In Fuel cells _____ are used as catalysts

Zinc - Mercury

Lead - Manganese

Platinum - Palladium

Nickel - Cadmium

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

H₂ + ½O₂ → H₂O

📚 Problem Solving Strategy

Identify catalyst types

Consider electrode reactions

Pt-Pd best for H₂ oxidation

⚠️ Common Mistakes

Confusing different metal catalysts

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Noble metals are best catalysts

This is some text inside of a div block.

💡 Key Formula

H₂ + ½O₂ → H₂O

📚 Problem Solving Strategy

Identify catalyst types

Consider electrode reactions

Pt-Pd best for H₂ oxidation

⚠️ Common Mistakes

Confusing different metal catalysts

Which of the following colligative properties can provide molar mass of proteins, polymers, and colloids with greater precision?

Depression in freezing point

Osmotic pressure

Relative lowering of vapour pressure

Elevation in boiling point

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

π = MRT (van't Hoff equation)

📚 Problem Solving Strategy

Compare properties

Consider molecular size effect

Osmotic pressure most sensitive

⚠️ Common Mistakes

Confusing different colligative properties

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

π = MRT relationship

This is some text inside of a div block.

💡 Key Formula

π = MRT (van't Hoff equation)

📚 Problem Solving Strategy

Compare properties

Consider molecular size effect

Osmotic pressure most sensitive

⚠️ Common Mistakes

Confusing different colligative properties

An aqueous solution of alcohol contains 18g of water and 414g of ethyl alcohol. The mole fraction of water is

0.7

0.9

0.1

0.4

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

X(water) = n(water)/(n(water) + n(alcohol))

📚 Problem Solving Strategy

Calculate moles of each component

Find total moles

Calculate mole fraction

⚠️ Common Mistakes

Confusing mass and mole ratios

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Mole fraction = moles of component/total moles

This is some text inside of a div block.

💡 Key Formula

X(water) = n(water)/(n(water) + n(alcohol))

📚 Problem Solving Strategy

Calculate moles of each component

Find total moles

Calculate mole fraction

⚠️ Common Mistakes

Confusing mass and mole ratios

Half-life of a reaction is found to be inversely proportional to the fifth power of initial concentration, the order of reaction is

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

t₁/₂ ∝ 1/a⁵ → n = 6

📚 Problem Solving Strategy

Use formula: t₁/₂ ∝ 1/aⁿ⁻¹

If t₁/₂ ∝ 1/a⁵, then n-1 = 5

n = 6

⚠️ Common Mistakes

Forgetting to add 1 to power

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Order = power + 1

This is some text inside of a div block.

💡 Key Formula

t₁/₂ ∝ 1/a⁵ → n = 6

📚 Problem Solving Strategy

Use formula: t₁/₂ ∝ 1/aⁿ⁻¹

If t₁/₂ ∝ 1/a⁵, then n-1 = 5

n = 6

⚠️ Common Mistakes

Forgetting to add 1 to power

For nth of reaction, Half-life period is directly proportional to

aⁿ⁻¹

a¹⁻ⁿ

1/aⁿ⁻¹

1/a¹⁻ⁿ

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

t₁/₂ ∝ 1/aⁿ⁻¹

📚 Problem Solving Strategy

Write half-life formula for nth order

t₁/₂ ∝ 1/aⁿ⁻¹

Check given options

⚠️ Common Mistakes

Confusing power relationships

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Half-life depends on initial concentration for orders other than first

This is some text inside of a div block.

💡 Key Formula

t₁/₂ ∝ 1/aⁿ⁻¹

📚 Problem Solving Strategy

Write half-life formula for nth order

t₁/₂ ∝ 1/aⁿ⁻¹

Check given options

⚠️ Common Mistakes

Confusing power relationships

Specific conductance of 0.1 M HNO₃ is 6.3×10⁻² ohm⁻¹ cm⁻¹. The molar conductance of the solution is

6.300 ohm⁻¹ cm² mol⁻¹

63.0 ohm⁻¹ cm² mol⁻¹

630 ohm⁻¹ cm² mol⁻¹

315 ohm⁻¹ cm² mol⁻¹

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Λₘ = (1000 × κ)/M

📚 Problem Solving Strategy

Use formula: Λₘ = (1000 × κ)/M

Λₘ = (1000 × 6.3×10⁻²)/0.1

Λₘ = 630 ohm⁻¹ cm² mol⁻¹

⚠️ Common Mistakes

Forgetting to multiply by 1000

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Remember to multiply by 1000 for conversion to molar conductance

This is some text inside of a div block.

💡 Key Formula

Λₘ = (1000 × κ)/M

📚 Problem Solving Strategy

Use formula: Λₘ = (1000 × κ)/M

Λₘ = (1000 × 6.3×10⁻²)/0.1

Λₘ = 630 ohm⁻¹ cm² mol⁻¹

⚠️ Common Mistakes

Forgetting to multiply by 1000

For spontaneity of a cell, which is correct?

ΔG = +ve, ΔE = +ve

ΔG = -ve

ΔG = 0, ΔE = 0

ΔG = -ve, ΔE = 0

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

ΔG = -nFE

📚 Problem Solving Strategy

Recall relationship between ΔG and spontaneity

ΔG must be negative for spontaneous process

ΔG = -nFE

⚠️ Common Mistakes

Confusing sign conventions

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

For spontaneous process, ΔG must be negative

This is some text inside of a div block.

💡 Key Formula

ΔG = -nFE

📚 Problem Solving Strategy

Recall relationship between ΔG and spontaneity

ΔG must be negative for spontaneous process

ΔG = -nFE

⚠️ Common Mistakes

Confusing sign conventions

The rate of the reaction CH₃COOC₂H₅ + NaOH → CH₃COONa + C₂H₅OH is given by Rate = K[CH₃COOC₂H₅][NaOH]. If concentration is expressed in mol L⁻¹, the unit of K is

L mol⁻¹ s⁻¹

s⁻¹

mol L s⁻¹

molL⁻¹ s⁻¹

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

K = Rate/[A][B] for 2nd order

📚 Problem Solving Strategy

Identify order of reaction from rate equation

Total order = 1 + 1 = 2

Units for 2nd order = L mol⁻¹ s⁻¹

⚠️ Common Mistakes

Forgetting to consider total order when determining units

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Rate constant units depend on overall order of reaction

This is some text inside of a div block.

💡 Key Formula

K = Rate/[A][B] for 2nd order

📚 Problem Solving Strategy

Identify order of reaction from rate equation

Total order = 1 + 1 = 2

Units for 2nd order = L mol⁻¹ s⁻¹

⚠️ Common Mistakes

Forgetting to consider total order when determining units

A first order reaction is half completed in 45 min. How long does it need 99.9% of the reaction to be completed?

10 Hours

20 Hours

5 Hours

7.5 Hours

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

t₉₉.₉% = 10t₅₀%; k = 0.693/t₅₀%

📚 Problem Solving Strategy

For first order reaction, t₉₉.₉% = 10t₅₀%

t₅₀% = 45 min

10 × 45 min = 450 min = 7.5 hours

⚠️ Common Mistakes

Students often forget to convert minutes to hours

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

First order reaction half-life is independent of concentration

This is some text inside of a div block.

💡 Key Formula

t₉₉.₉% = 10t₅₀%; k = 0.693/t₅₀%

📚 Problem Solving Strategy

For first order reaction, t₉₉.₉% = 10t₅₀%

t₅₀% = 45 min

10 × 45 min = 450 min = 7.5 hours

⚠️ Common Mistakes

Students often forget to convert minutes to hours

Resistance of 0.1M weak acid HA in conductivity cell is 2×10³Ω. Cell constant 0.78cm⁻¹ and λ°m=390Scm²mol⁻¹. pH of solution is

3.3

4.2

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

pH = -log[H⁺]

📚 Problem Solving Strategy

Calculate conductivity

Find degree of ionization

Calculate pH

⚠️ Common Mistakes

Conductance calculation confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

κ = G*/R

This is some text inside of a div block.

💡 Key Formula

pH = -log[H⁺]

📚 Problem Solving Strategy

Calculate conductivity

Find degree of ionization

Calculate pH

⚠️ Common Mistakes

Conductance calculation confusion

In which reaction rate constant has unit molL⁻¹s⁻¹

2NO(g) + O₂(g) → 2NO₂(g)

Decomposition of HI on Gold surface

Acid hydrolysis of CH₃COOCH₃

CHCl₃ + Cl₂ → CCl₄ + HCl

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Zero order kinetics

📚 Problem Solving Strategy

Check reaction order

Analyze units

Identify zero order

⚠️ Common Mistakes

Rate constant unit confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Rate = k[A]⁰

This is some text inside of a div block.

💡 Key Formula

Zero order kinetics

📚 Problem Solving Strategy

Check reaction order

Analyze units

Identify zero order

⚠️ Common Mistakes

Rate constant unit confusion

During electrolysis of brine using inert electrodes

Na deposits on cathode

Cl₂ liberates at anode

O₂ liberates at anode

H₂ liberates at anode

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

2Cl⁻ → Cl₂ + 2e⁻

📚 Problem Solving Strategy

Consider electrode reactions

Check standard potentials

Analyze products

⚠️ Common Mistakes

Product prediction confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Preferential discharge

This is some text inside of a div block.

💡 Key Formula

2Cl⁻ → Cl₂ + 2e⁻

📚 Problem Solving Strategy

Consider electrode reactions

Check standard potentials

Analyze products

⚠️ Common Mistakes

Product prediction confusion

Consider 4 electrodes: Ag⁺(0.0001M)/Ag(s), Ag⁺(0.1M)/Ag(s), Ag⁺(0.01M)/Ag(s), Ag⁺(0.001M)/Ag(s); E°Ag⁺/Ag=0.80V. Reduction potential order is

A < D < C < B

A < B < C < D

B < C < D < A

C < D < A < B

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Concentration effect

📚 Problem Solving Strategy

Use Nernst equation

Calculate potentials

Arrange in order

⚠️ Common Mistakes

Concentration effect confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

E = E° + (0.059/n)log[M⁺]

This is some text inside of a div block.

💡 Key Formula

Concentration effect

📚 Problem Solving Strategy

Use Nernst equation

Calculate potentials

Arrange in order

⚠️ Common Mistakes

Concentration effect confusion

Rate constants k₁=10¹⁶e⁻²⁰⁰⁰/T and k₂=10¹⁵e⁻¹⁰⁰⁰/T. Temperature at which k₁=k₂ is

1000/2.303 K

1000 K

2000/2.303 K

2000 K

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

T = 1000/2.303

📚 Problem Solving Strategy

Equate k₁ and k₂

Take ln

Solve for T

⚠️ Common Mistakes

Equation solving confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

ln(10¹⁶/10¹⁵) = (2000-1000)/T

This is some text inside of a div block.

💡 Key Formula

T = 1000/2.303

📚 Problem Solving Strategy

Equate k₁ and k₂

Take ln

Solve for T

⚠️ Common Mistakes

Equation solving confusion

For a reaction, rate constant at 300K is 6.0×10⁻⁵s⁻¹. Value of Arrhenius factor A at infinitely high temperature is

6×10⁻⁵/300

6×10⁵

6×10⁵×e⁻Ea/300R

e⁻Ea/300R

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

k = 6×10⁻⁵ = Ae⁻Ea/300R

📚 Problem Solving Strategy

Use Arrhenius equation

Consider T→∞

Solve for A

⚠️ Common Mistakes

Temperature effect confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

k = Ae⁻Ea/RT

This is some text inside of a div block.

💡 Key Formula

k = 6×10⁻⁵ = Ae⁻Ea/300R

📚 Problem Solving Strategy

Use Arrhenius equation

Consider T→∞

Solve for A

⚠️ Common Mistakes

Temperature effect confusion

A sample of water is found to contain 5.85%(w/w) of AB (molecular mass 58.5) and 9.50%(w/w) XY₂ (molecular mass 95). Assuming 80% ionisation of AB and 60% ionisation of XY₂, the freezing point of water sample is [Given: Kf for water 1.86K kg mol⁻¹, Freezing point of pure water is 273K and A,B and Y are monovalent ions]

280.44 K

281.75 K

264.25 K

265.56 K

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

ΔTf calculations

📚 Problem Solving Strategy

Calculate molality

Find van't Hoff factor

Apply ΔTf formula

⚠️ Common Mistakes

Depression calculation

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

ΔTf = Kf×m×i

This is some text inside of a div block.

💡 Key Formula

ΔTf calculations

📚 Problem Solving Strategy

Calculate molality

Find van't Hoff factor

Apply ΔTf formula

⚠️ Common Mistakes

Depression calculation

Dimerisation of solute molecules in low dielectric constant solvent is due to

Co-ordinate bond

Ionic bond

Hydrogen bond

Covalent bond

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

H-bonding

📚 Problem Solving Strategy

Consider interactions

Check solvent effect

Analyze bond type

⚠️ Common Mistakes

Bond type confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Intermolecular forces

This is some text inside of a div block.

💡 Key Formula

H-bonding

📚 Problem Solving Strategy

Consider interactions

Check solvent effect

Analyze bond type

⚠️ Common Mistakes

Bond type confusion

Salt water reduces swelling in feet due to

Edema

Diffusion

Reverse Osmosis

Osmosis

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

H₂O moves to concentrated solution

📚 Problem Solving Strategy

Consider concentration

Check water movement

Analyze process

⚠️ Common Mistakes

Process direction confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Higher salt concentration

This is some text inside of a div block.

💡 Key Formula

H₂O moves to concentrated solution

📚 Problem Solving Strategy

Consider concentration

Check water movement

Analyze process

⚠️ Common Mistakes

Process direction confusion

A 30% solution of hydrogen peroxide is

50 volume' hydrogen peroxide

100 volume' hydrogen peroxide

30 volume' hydrogen peroxide

10 volume' hydrogen peroxide

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

H₂O₂ → H₂O + ½O₂

📚 Problem Solving Strategy

Convert percentage

Calculate volume

Apply formula

⚠️ Common Mistakes

Volume strength confusion

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

1mL gives x mL O₂

This is some text inside of a div block.

💡 Key Formula

H₂O₂ → H₂O + ½O₂

📚 Problem Solving Strategy

Convert percentage

Calculate volume

Apply formula

⚠️ Common Mistakes

Volume strength confusion

For which one of the following mixtures is composition uniform throughout?

Sand and water

Grains and pulses with stones

Mixture of oil and water

Dilute aqueous solution of sugar

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

No formula involved.

📚 Problem Solving Strategy

Homogeneous mixtures have uniform composition throughout.

Aqueous sugar solution dissolves uniformly without phase separation.

Final Answer: Option D; sugar solution is homogeneous.

⚠️ Common Mistakes

Assuming phase-separated mixtures like oil and water to be uniform.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Differentiate between homogeneous and heterogeneous mixtures.

This is some text inside of a div block.

💡 Key Formula

No formula involved.

📚 Problem Solving Strategy

Homogeneous mixtures have uniform composition throughout.

Aqueous sugar solution dissolves uniformly without phase separation.

Final Answer: Option D; sugar solution is homogeneous.

⚠️ Common Mistakes

Assuming phase-separated mixtures like oil and water to be uniform.

Which one of the following does not represent Arrhenius equation?

Ea log k = log A / 2.303RT

k = Ae^(-Ea/RT)

Ea/RT = ln A - ln k

k = Ae^(Ea/RT)

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

k = Ae^(-Ea/RT) and related variations.

📚 Problem Solving Strategy

Recognize the valid forms of Arrhenius equation.

Compare all forms of the equation. The correct forms involve negative exponential or logarithmic terms.

Final Answer: Option D does not match the equation.

⚠️ Common Mistakes

Misinterpreting positive exponents as valid forms.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Recall valid mathematical forms of Arrhenius equation.

This is some text inside of a div block.

💡 Key Formula

k = Ae^(-Ea/RT) and related variations.

📚 Problem Solving Strategy

Recognize the valid forms of Arrhenius equation.

Compare all forms of the equation. The correct forms involve negative exponential or logarithmic terms.

Final Answer: Option D does not match the equation.

⚠️ Common Mistakes

Misinterpreting positive exponents as valid forms.

For the reaction PCl₅ → PCl₃ + Cl₂, rate and rate constant are 1.02 × 10⁻⁴ mol/L/s and 3.4 × 10⁻⁵ s⁻¹ respectively. What is [PCl₅]?

8.0 mol/L

3.0 mol/L

0.2 mol/L

2.0 mol/L

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Rate = k[Reactant].

📚 Problem Solving Strategy

Use the formula Rate = k[PCl₅].

Rearrange to find [PCl₅]: [PCl₅] = Rate / k = (1.02 × 10⁻⁴) / (3.4 × 10⁻⁵).

Final Answer: [PCl₅] = 3.0 mol/L.

⚠️ Common Mistakes

Forgetting to divide rate by rate constant or misplacing units.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Relate rate and rate constant to molarity.

This is some text inside of a div block.

💡 Key Formula

Rate = k[Reactant].

📚 Problem Solving Strategy

Use the formula Rate = k[PCl₅].

Rearrange to find [PCl₅]: [PCl₅] = Rate / k = (1.02 × 10⁻⁴) / (3.4 × 10⁻⁵).

Final Answer: [PCl₅] = 3.0 mol/L.

⚠️ Common Mistakes

Forgetting to divide rate by rate constant or misplacing units.

For the reaction A ⇌ B, Ea = 50 kJ mol⁻¹ and ΔH = -20 kJ mol⁻¹. After catalyst decreases Ea by 10 kJ mol⁻¹, find Ea (backward)

60 kJ mol⁻¹

40 kJ mol⁻¹

70 kJ mol⁻¹

20 kJ mol⁻¹

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

ΔH = Ea(f) - Ea(b).

📚 Problem Solving Strategy

Use the relation ΔH = Ea(f) - Ea(b).

Ea(forward) = 50 - 10 = 40 kJ/mol. Hence Ea(backward) = ΔH + Ea(f) = -20 + 40 = 60 kJ/mol.

Final Answer: Ea(backward) = 60 kJ/mol.

⚠️ Common Mistakes

Incorrectly assuming ΔH = Ea without considering catalyst effect.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Understand catalyst effects on Ea.

This is some text inside of a div block.

💡 Key Formula

ΔH = Ea(f) - Ea(b).

📚 Problem Solving Strategy

Use the relation ΔH = Ea(f) - Ea(b).

Ea(forward) = 50 - 10 = 40 kJ/mol. Hence Ea(backward) = ΔH + Ea(f) = -20 + 40 = 60 kJ/mol.

Final Answer: Ea(backward) = 60 kJ/mol.

⚠️ Common Mistakes

Incorrectly assuming ΔH = Ea without considering catalyst effect.

How many Coulombs are required to oxidise 0.1 mole of H2O to oxygen?

1.93 × 10^5 C

1.93 × 10^4 C

3.86 × 10^4 C

9.65 × 10^3 C

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

q = n × F (Faraday constant).

📚 Problem Solving Strategy

Oxidation of water to oxygen involves 4 electrons per molecule.

For 0.1 mole of H2O: (0.1 × 2 × 96500 = 1.93 × 10^4 C).

Final Answer: 1.93 × 10^4 C.

⚠️ Common Mistakes

Mixing up electron moles or Faraday's constant during calculations.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Use Faraday's Laws of Electrolysis.

This is some text inside of a div block.

💡 Key Formula

q = n × F (Faraday constant).

📚 Problem Solving Strategy

Oxidation of water to oxygen involves 4 electrons per molecule.

For 0.1 mole of H2O: (0.1 × 2 × 96500 = 1.93 × 10^4 C).

Final Answer: 1.93 × 10^4 C.

⚠️ Common Mistakes

Mixing up electron moles or Faraday's constant during calculations.

Vapour pressure of a solution containing 18 g of glucose and 178.2 g of water at 100°C is...

76.0 torr

752.0 torr

7.6 torr

3207.6 torr

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

P_solution = P_water × (1 - χ_solute).

📚 Problem Solving Strategy

Use Raoult’s law: P_solution = P_water × (1 - χ_solute).

Calculate χ_solute = moles of solute / (moles of solute + moles of solvent).

Result: P_solution = 760 - 7.6 = 752.4 torr.

⚠️ Common Mistakes

Incorrect mole calculation for glucose or water.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Understand Raoult's law application.

This is some text inside of a div block.

💡 Key Formula

P_solution = P_water × (1 - χ_solute).

📚 Problem Solving Strategy

Use Raoult’s law: P_solution = P_water × (1 - χ_solute).

Calculate χ_solute = moles of solute / (moles of solute + moles of solvent).

Result: P_solution = 760 - 7.6 = 752.4 torr.

⚠️ Common Mistakes

Incorrect mole calculation for glucose or water.

A current of 3A is passed through molten calcium salt for 1 hr 47 min 13 sec. The mass of calcium deposited is...

6.0 g

2.0 g

8.0 g

4.0 g

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

Mass = (E × I × t) / 96500.

📚 Problem Solving Strategy

Use Faraday’s law: Mass deposited = (E × I × t) / 96500.

Substituting values: E = 40, I = 3A, t = 6432 s. Result: (40 × 3 × 6432) / 96500 = 3.99 g ≈ 4.0 g.

Final Mass: 4.0 g.

⚠️ Common Mistakes

Errors in time conversion or forgetting valency of calcium during calculations.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Apply Faraday's Law to time-dependent mass calculations.

This is some text inside of a div block.

💡 Key Formula

Mass = (E × I × t) / 96500.

📚 Problem Solving Strategy

Use Faraday’s law: Mass deposited = (E × I × t) / 96500.

Substituting values: E = 40, I = 3A, t = 6432 s. Result: (40 × 3 × 6432) / 96500 = 3.99 g ≈ 4.0 g.

Final Mass: 4.0 g.

⚠️ Common Mistakes

Errors in time conversion or forgetting valency of calcium during calculations.

A mixture of phenol and aniline shows negative deviation from Raoult's law. This is because of:

Polar covalent bond

Non-polar covalent bond

Intermolecular hydrogen bond

Intramolecular hydrogen bond

🥳 Wohoo! Correct answer

This is some text inside of a div block.

💡 Key Formula

No formula involved.

📚 Problem Solving Strategy

The negative deviation is due to strong intermolecular hydrogen bonding between phenol and aniline.

Phenol and aniline form stronger intermolecular bonds than with their individual molecules.

Result: Negative deviation due to intermolecular hydrogen bonding.

⚠️ Common Mistakes

Assuming polar or non-polar covalent bonds cause deviation.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Recall the nature of molecular interactions.

This is some text inside of a div block.

💡 Key Formula

No formula involved.

📚 Problem Solving Strategy

The negative deviation is due to strong intermolecular hydrogen bonding between phenol and aniline.

Phenol and aniline form stronger intermolecular bonds than with their individual molecules.

Result: Negative deviation due to intermolecular hydrogen bonding.

⚠️ Common Mistakes

Assuming polar or non-polar covalent bonds cause deviation.

The value of 'A' in the equation λ_m = λ_0 - A √C is same for the pair...

NaCl and CaCl2

CaCl2 and MgSO4

NaCl and KBr

MgCl2 and NaCl

🥳 Wohoo! Correct answer

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💡 Key Formula

λ_m = λ_0 - A √C (empirical relation).

📚 Problem Solving Strategy

A depends on ion type and interactions in solution.

NaCl and KBr have similar ionic types and interaction effects.

Result: Value of A is identical for NaCl and KBr.

⚠️ Common Mistakes

Assuming all salts affect A equally regardless of charge or type.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Relate ionic properties to conductivity coefficients.

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💡 Key Formula

λ_m = λ_0 - A √C (empirical relation).

📚 Problem Solving Strategy

A depends on ion type and interactions in solution.

NaCl and KBr have similar ionic types and interaction effects.

Result: Value of A is identical for NaCl and KBr.

⚠️ Common Mistakes

Assuming all salts affect A equally regardless of charge or type.

Which of the following pairs will show positive deviation from Raoult's Law?

Water-HCl

Benzene-Methanol

Water-HNO3

Acetone-Chloroform

🥳 Wohoo! Correct answer

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💡 Key Formula

None (Conceptual).

📚 Problem Solving Strategy

Positive deviation occurs when intermolecular forces are weaker in the solution than in pure components.

Benzene and methanol have weak interactions compared to their pure molecular interactions.

Final Answer: Benzene-methanol shows positive deviation.

⚠️ Common Mistakes

Confusing positive deviation as stronger interactions between solute and solvent.

😢 Uh oh! Incorrect answer, Try again

🗝 Hint

Recall weaker molecular interactions.

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💡 Key Formula

None (Conceptual).

📚 Problem Solving Strategy

Positive deviation occurs when intermolecular forces are weaker in the solution than in pure components.

Benzene and methanol have weak interactions compared to their pure molecular interactions.

Final Answer: Benzene-methanol shows positive deviation.

⚠️ Common Mistakes

Confusing positive deviation as stronger interactions between solute and solvent.