WAEC Chemistry Past Questions & Answers - Page 269

1,341.

What is the quantity of electricity produced when a current of 0.5A is passed for 5 hours 45 mins? (1F = 96500C)

A.

0. 11F

B.

0.12F

C.

0.22F

D.

1.1F

E.

2.2F

Correct answer is A

No explanation has been provided for this answer.

1,342.

The scum formed when soap is mixed with hard water could be

A.

calcium trioxocarbonate (IV)

B.

propane- 1, 2, 3 - triol

C.

calcium hydrogentrioxocarbonate (IV)

D.

magnesium tetraoxosulphate (IV)

E.

calcium stearate

Correct answer is A

No explanation has been provided for this answer.

1,343.

The halide used widely in photography is

A.

ammonium chloride

B.

calcum chloride

C.

silver bromide

D.

sodium brmide

E.

aluminium fluroide

Correct answer is C

No explanation has been provided for this answer.

1,344.

When air is passed through potash and then pyrogallol, the components are noble gases

A.

oxygen and carbon (IV) oxide

B.

oxygen and nitrogen

C.

nitrogen and water vapour

D.

water vapour and carbon (IV) oxide

E.

oxygen and water vapour

Correct answer is C

No explanation has been provided for this answer.

1,345.

The reactions ethyne are mainly

A.

substitution reactions

B.

addition reactions

C.

addition polymerization

D.

catalytic hydrogenation

E.

catalytic halogenation

Correct answer is B

No explanation has been provided for this answer.