Only Toppers Survive This Grade 12th Chemistry Quiz: Electro Chem

1. The laws of electrolysis were enunciated first by …

Dalton

Faraday

Kekule

Avogadro

2. Faraday's laws of electrolysis are related to …

Atomic number of the cation

Atomic number of the anion

Equivalent weight of the electrolyte

Speed of the cation

3. A solution which is resistant to changes of pH on addition of small amounts of an acid or a base is known as:

Buffer solution

True solution

Isohydric solution

Ideal solution

4. The process in which chemical change occurs on passing electricity is termed as …

Neutralisation

Hydrolysis

Electrolysis

Ionisation

5. Ostwald's dilution law is applicable in the case of the solution of

CH₃COOH

NaCl

NaOH

H₂SO₄

6. When one coulomb of electricity is passed through an electrolytic solution, the mass deposited on the electrode is equal to …

Equivalent weight

Molecular weight

Electro‑chemical equivalent

One gram

7. NH₄OH is a weak base because

It has low vapour pressure

It is only partially ionized.

It is completely ionized.

It has low density

8. Indicators used in acid–base titrations are …

Strong organic acids

Strong organic bases

Weak organic acids or weak organic bases

Non‑electrolytes

9. For the titration between oxalic acid and sodium hydroxide, the indicator used is …

Potassium permanganate

Phenolphthalein

Litmus

Methyl orange

10. When the pH of a solution is 2, the hydrogen ion concentration (in moles L⁻¹) is

1 x 10-12

1 x 10-2

1 x 10-7

1 x 10-4

11. Which one of the following formulae represents Ostwald's dilution law for a binary electrolyte whose degree of dissociation is alpha and concentration C.

K = (1 - alpha) * C / alpha

K = alpha2 * C / (1 - alpha)

K = (1 - alpha) * C / alpha2

K = alpha2 * C / ((1 - alpha) * C)

12. Which one of the following relationships is correct ?

PH = 1 / [H+]

PH = log₁₀[H+]

Log10 pH = [H+]

PH = log₁₀ (1 / [H+])

13. The hydrogen ion concentration of a buffer solution consisting of a weak acid and its salt is given by

H+ = Ka * [Acid] / [Salt]

H+ = Ka * [Salt] / [Acid]

H+ = Ka * [Acid]

H+ = Ka * [Salt]

14. The specific conductance of a 0.01 M solution of KCl is 0.0014 ohm⁻¹ cm⁻¹ at 25 C. Its equivalent conductance is:

14 ohm^-1 cm^2 eq^-1

140 ohm^-1 cm^2 eq^-1

1.4 ohm^-1 cm^2 eq^-1

0.14 ohm^-1 cm^2 eq^-1

15. The equivalent conductivity of CH₃COOH at 24 C is 80 ohm⁻¹ cm² eq⁻¹ and at infinite dilution 400 ohm⁻¹ cm² eq⁻¹.. The degree of dissociation of CH₃COOH is

1

0.2

0.1

0.3