WAEC Chemistry Past Questions & Answers - Page 183

911.

Glucose gives a brick-red precipitate with Fehling's solution because it is

A.

carbohydrate

B.

an alkanoate

C.

a reducing sugar

D.

a non-electrolyte

Correct answer is C

No explanation has been provided for this answer.

912.

A solution of zinc chloride should not be stored in a container made of

A.

tin

B.

copper

C.

aluminium

D.

lead

Correct answer is C

No explanation has been provided for this answer.

913.

Two solutions containing Pb2+ and AI3+ respectively can be distingusihed using

A.

NaOH(aq)

B.

NH3(aq)

C.

conc. HCI3

D.

conc. HCI

Correct answer is D

No explanation has been provided for this answer.

914.

What quantity of electrons in moles is needed to discharge two moles of aluminum from aluminum oxide (AI 2O3)

A.

1

B.

2

C.

4

D.

6

Correct answer is D

One mole of aluminium from aluminium oxide gives three elecrrons. Two moles of aluminium from aluminium oxide give six electrons

915.

Which of the following subtances will not produce effervescence with dilute hydeochloric acid?

A.

Copper (ll) trioxocarbonate (IV)

B.

Potassium hydrogentrioxocarbonate (lV)

C.

Zinc granules

D.

Sodium chloride

Correct answer is D

No explanation has been provided for this answer.