Question 591:

• 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 592:

• 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 593:

• 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-

Question 594:

• JAMB 1989

An element, Z froms an anion whose formula is [Z(CN)₆]^y. If Z has an oxidation number of +2, what is the value of y?

A. - 2
B. - 3
C. - 4
D. - 5

Question 595:

• JAMB 1989

The combustion of ethene, C ₂H ₄, is given by the equation C ₂H ₄ + 30 ₂ → 2CO₂ + 2H₂ O; ∆H = - 1428 KJ. If the molar heats of formation of water and carbon (IV) oxide are - 286 kJ and - 396 kJ respectively, calculate the molar heat of formation of ethene in KJ

A. - 2792
B. + 2792
C. - 64
D. + 64