10-minute Quiz : Chapter 17 Strength of acids and alkalis

The strength of an alkali depends on

• A. the number of hydrogen atoms each molecule of an alkali has.

• B. the number of hydroxide ions produced per molecule of an alkali when dissolved in water.

• C. its extent of ionization or dissociation in water.

• D. the rate of forming salts when reacting with acids.

Which of the following acids are weak acids?

(1) Citric acid

(2) Carbonic acid

(3) Sulphurous acid

• A. (1) and (2) only

• B. (1) and (3) only

• C. (2) and (3) only

• D. (1), (2) and (3)

Consider the four solutions below:

(1)：0.1 M HCl(aq)

(2)：1.0 M HCl(aq)

(3)：0.1 M CH₃COOH(aq)

(4)：1.0 M H₂SO₄(aq)

Which of the following represents the solutions arranged in increasing pH?

• A. (1), (2), (3), (4)

• B. (2), (4), (1), (3)

• C. (3), (1), (2), (4)

• D. (4), (2), (1), (3)

30 cm³ of 0.10 M sulphuric acid is mixed with 40 cm³ of 0.15 M aqueous ammonia. Which of the following relationships about [H⁺(aq)] and [OH⁻(aq)] in the resultant solution is correct?

• A. [H⁺(aq)] < [OH⁻(aq)]

• B. [H⁺(aq)] > [OH⁻(aq)]

• C. [H⁺(aq)] = [OH⁻(aq)]

• D. [H⁺(aq)] = 2[OH⁻(aq)]

Which of the following would increase the pH of 0.1 M aqueous ammonia?

(1) Adding 0.1 M sodium hydroxide solution

(2) Adding solid sodium chloride

(3) Adding a small amount of water

• A. (1) only

• B. (2) only

• C. (1) and (3) only

• D. (2) and (3) only

The pH of solutions X and Y are 2 and 1 respectively. 50 cm³ of solution X is mixed with 50 cm³ of solution Y. What is the pH of the resultant solution?

• A. 0.74

• B. 1.3

• C. 1.5

• D. 1.8

It is known that the pH of a sample of acid X and that of a sample of acid Y are both 3.5. Which of the following statements MUST be correct?

(1) The two samples have the same concentration of H⁺(aq) ions.

(2) X and Y are of the same basicity.

(3) X and Y are of the same strength.

• A. (1) only

• B. (2) only

• C. (1) and (3) only

• D. (2) and (3) only

Given that HX is a weak acid, which of the following statements about 0.10 M HX is correct?

• A. The concentration of H⁺(aq) in the acid is 0.10 M.

• B. The concentration of X⁻(aq) in the acid is 0.10 M.

• C. The concentration of HX(aq) in the acid is higher than that of H⁺(aq).

• D. The pH of the acid is 1.

Which of the following species has the highest molarity in dilute phosphoric acid?

• A. H₃PO₄(aq)

• B. H⁺(aq)

• C. PO₄⁻(aq)

• D. OH⁻(aq)

It is known that alkali X is stronger than alkali Y. Which of the following combinations about 0.1 M aqueous solutions of X and Y are correct?

• A. (1) and (2) only

• B. (1) and (3) only

• C. (2) and (3) only

• D. (1), (2) and (3)