10-minute Quiz : Chapter 19

25.0 cm³ of a dibasic acid requires 36.25 cm³ of 1.0 M sodium hydroxide solution for complete neutralization. What is the molarity of the acid?

• A. 0.59 M

• B. 0.73 M

• C. 1.00 M

• D. 1.45 M

A student prepared 250.0 cm³ of 0.010 M sodium carbonate solution from 0.10 M sodium carbonate solution by dilution. The student used apparatus X to transfer 25.0 cm³ of 0.10 M sodium carbonate solution to apparatus Y, then add distilled water up to the graduation mark. Which of the following combinations about apparatus X and Y is correct?

• A

• B

• C

• D

3.50 g of a limestone sample is dissolved in 150 cm³ of 0.50 M hydrochloric acid. The excess acid requires 20.10 cm³ of 1.00 M sodium carbonate solution for complete reaction. What is the percentage by mass of calcium carbonate in the limestone sample?

(Assume that all other substances in the limestone sample react with neither hydrochloric acid nor sodium carbonate solution.)

(Relative atomic masses: C = 12.0, O = 16.0, Ca = 40.1)

• A. 28.8%

• B. 49.8%

• C. 57.5%

• D. 99.5%

A potassium carbonate solution requires 20.00 cm³ of 0.05 mol dm⁻³ hydrochloric acid for complete reaction. Which of the following combinations about the volume and concentration of the potassium carbonate solution is correct?

• A

• B

• C

• D

Phosphorus pentachloride and water react according to the following equation:

PCl₅(s) + 4H₂O(ℓ) → H₃PO₄(aq) + 5HCl(aq)

1.04 g of phosphorus pentachloride is dissolved in distilled water and made up to a 100.0 cm³ solution. What is the concentration of hydrochloric acid in this solution?

(Molar mass of PCl₅ = 208 g mol⁻¹)

• A. 0.0100 mol dm⁻³

• B. 0.0500 mol dm⁻³

• C. 0.250 mol dm⁻³

• D. 2.50 mol dm⁻³

Dilute barium hydroxide solution is added from a burette, 5.0 cm³ at a time, to 25 cm³ of dilute sulphuric acid in a conical flask until in excess. The electrical conductivity of the mixture formed

• A. increases steadily.

• B. decreases steadily.

• C. increases and then decreases.

• D. decreases and then increases.

Consider the following reaction:

NaHSO₄(aq) + NaOH(aq) → Na₂SO₄(aq) + H₂O(ℓ)

0.0100 mol of sodium hydrogensulphate solution completely reacts with 0.200 M sodium hydroxide solution. What is the volume of sodium hydroxide solution used?

• A. 20.0 cm³

• B. 50.0 cm³

• C. 100 cm³

• D. 500 cm³

In a titration experiment, 0.10 M sodium hydroxide solution is added slowly to 0.10 M hydrochloric acid. The variation of pH of the solution is monitored by using a data-logger with a pH sensor. The titration curve for the titration is shown below. Which of the points in the graph indicates the equivalence point of the titration?

• A. I

• B. II

• C. III

• D. IV

Consider the following reaction:

MgO(s) + 2HNO₃(aq) → Mg(NO₃)₂(aq) + H₂O(ℓ)

2.0 g of magnesium oxide completely reacts with 50.0 cm³ of a nitric acid. What is the molarity of the nitric acid?

(Relative atomic masses: O = 16.0, Mg = 24.3)

• A. 0.002 mol dm⁻³

• B. 0.008 mol dm⁻³

• C. 2.0 mol dm⁻³

• D. 8.0 mol dm⁻³

25 cm³ of 0.10 mol dm⁻³ hydrochloric acid is mixed with 20 cm³ of 0.12 mol dm⁻³ sodium hydroxide solution. What is the pH of the resultant solution?

• A. 0.53

• B. 0.96

• C. 1.3

• D. 2.7