JAMB Chemistry Past Questions & Answers - Page 357

1,781.

What happens when zinc rod is immersed in copper (II) tetraoxosulphate (VI) solution/

A.

The blue colour of the solution disappears

B.

Electrons flow from copper to zinc

C.

The zinc rod remain undissolved

D.

The copper generate more copper ions

Correct answer is A

No explanation has been provided for this answer.

1,782.

The reaction that takes place in Daniell cell is

A.

direct combination

B.

redox

C.

double decomposition

D.

neutralization

Correct answer is B

No explanation has been provided for this answer.

1,783.

H3PO4(aq) + H2O(l) ↔ H2PO4-(aq) + H3O+(aq)
ΔH = -13kJ at 298K
In the reaction above, an increase in temperature would

A.

slow downthe reverse reaction

B.

have no effect on the reaction

C.

favour the reverse reaction

D.

favour the forward reaction

Correct answer is C

No explanation has been provided for this answer.

1,784.

If chlorine is bubbled into water and the resulting yellowish-green solution is exposed to bright sunlight for a while, the solution will decompose giving out

A.

oxygen and leaving behind aqueous hydrochloric acid

B.

chlorine and oxygen

C.

oxygen, hydrogen and chlorine

D.

oxygen, thereby producing hypochlorous acid

Correct answer is A

No explanation has been provided for this answer.

1,785.

Which of the following sets of metals dissolves in dilute HCl?

A.

Fe, Sn and Cu

B.

Mg, Fe and Cu

C.

Mg, Sn and Fe

D.

Cu, Mg and Sn

Correct answer is C

No explanation has been provided for this answer.