WAEC Past Questions and Answers - Page 1815

9,071.

How many mole of AgNO 3 are there in 500cm3 of 0.01MAgNO3 solution?

A.

0.005 mole

B.

0.05 mole

C.

0.5 mole

D.

5 moles

E.

1 mole

Correct answer is A

No explanation has been provided for this answer.

9,072.

The following alloys contain copper except

A.

magnalium

B.

duralumn

C.

bronze

D.

brass

E.

type metal

Correct answer is A

No explanation has been provided for this answer.

9,073.

Which of the following equations represents the reaction leading to the removal of permanent hardness of water?

A.

Ca(HCO 3)2 → CaCO3 + H2O + CO2

B.

MgSO4 + Na 2CO3 + Na 2SO

C.

Ca(OH) 2 + 2HCI → CaCI 2 + 2H 2O

D.

Ca(HCO3)2 + Ca(OH)3 → 2CaCO3 + 2H2O

E.

MgSO4 + BaCI2 → MgCI2 + BaSO4

Correct answer is B

No explanation has been provided for this answer.

9,074.

In the reaction represented by the equation; 2FeCI3 + SO2 + 2H2O → 2FeCL2 + H2SO4 + 2HCI the oxidation number of sulphur changes from

A.

+2 to + 6

B.

+ 4 to + 6

C.

0 to + 6

D.

- 2 to + 4

E.

+2 to + 4

Correct answer is B

No explanation has been provided for this answer.

9,075.

Which of the following pollutants is biodegradable ?

A.

Sewage

B.

Plastics

C.

Metal scrape

D.

Lead compounds

E.

Hydrogen sulphide

Correct answer is A

No explanation has been provided for this answer.