WAEC Past Questions and Answers - Page 1808

9,036.

How many principal electronic shells has an atom whose electronic configuration is shown below? 1s22s22p63s1

A.

1

B.

2

C.

3

D.

4

E.

11

Correct answer is C

No explanation has been provided for this answer.

9,037.

Which of the following is not a direct petroleum product?

A.

Methane

B.

Ethanol

C.

Petrol

D.

Vaseline

E.

Kerosene

Correct answer is D

No explanation has been provided for this answer.

9,038.

Which of the reactions represented by the following equations will take place at room temperature?

A.

C 6 H2O → CO + H2

B.

CuO + H2 → Cu + H2O

C.

N2 + 3H2 → 2NH3

D.

2Na + 2H2O → 2NaOH + H2

E.

2Fe + 3CI2 → 2FeCI3

Correct answer is D

No explanation has been provided for this answer.

9,039.

When starch undergoes complete enzyme-catalyzed hydrolysis, the resulting product is

A.

glucose

B.

maltose

C.

sucrose

D.

fructose

E.

cellulose

Correct answer is A

No explanation has been provided for this answer.

9,040.

In the redox reaction represented by the following equation: Cu2+aq + Zn(s) → Cu(s) + Zn2+

A.

the oxidation number of copper increases

B.

copper (ll) ions are reduced to copper atoms

C.

zinc atoms are reduced to zinc ions

D.

copper (ll) ions donate electrons to zinc atoms

Correct answer is B

No explanation has been provided for this answer.