Jamb Chemistry 1989 Past Questions and Answers

Question 16:

• JAMB 1989

A solution of calcium bromide contains 20 g dm ³ What is the molarity of the solution with respect to calcium bromide and bromide ions? [Ca = 40, Br = 80]

A. 0. 1, 0 . 1
B. 0. 1, 0. 2
C. 0. 1, 0. 05
D. 0.05, 0.1

Question 17:

• JAMB 1989

The substance ZnO dissolves in sodium hydroxide solution and mineral acid solution to give soluble products in each case. ZnO is therefore referred to as

A. An allotropic oxide
B. An amphoteric oxide
C. A peroxide
D. A dioxide

Question 18:

• JAMB 1989

An acid and its conjugate base

A. Can neutralise each other to form a salt
B. Differ only by a proton
C. Differ only by the opposite charges they carry
D. Are always neutral substances

Question 19:

• JAMB 1989

The same current is passed for the same time through solutions of AgNO₃ and CuSO₄ connected in series. How much silver will be deposited if 1.0 g of copper is produced?
[Cu = 63.5, S = 32, O = 16, Ag = 108, N = 14]

A. 1.7 g
B. 3.4 g
C. 6. 8 g
D. 13. 6 g

Question 20:

• JAMB 1989

What is discharged at the cathode during the electrolysis of copper (ll) tetraoxosulphate (VI) solution?

A. Cu ²⁺ only
B. H [sup][/sup]+ only
C. Cu ²⁺ and H
D. Cu ²⁺ and SO ^2-