WAEC Chemistry Past Questions & Answers - Page 129

641.

In metallic colids, the forces of attraction are between the mobile valence electrons and

A.

atoms

B.

neutrons

C.

the negative ions

D.

positively charged nuclei

Correct answer is D

No explanation has been provided for this answer.

642.

When element 20A combines with element 8Y,

A.

a covalent compound, AY is formed

B.

an ionic compound AY is formed

C.

an ionic compound, A2Y is formed

D.

a covalent compound, AY2 is formed

Correct answer is B

No explanation has been provided for this answer.

643.

The bond formed when two electrons that are shared between two atoms are donated by only one of the atoms is

A.

covalent

B.

dative

C.

ionic

D.

metalic

Correct answer is B

No explanation has been provided for this answer.

644.

Which of the following elements can conveniently be placed in two groups in the periodic table ?

A.

Carbon

B.

Copper

C.

Hydrogen

D.

Oxygen

Correct answer is C

No explanation has been provided for this answer.

645.

Chlorine, bromine and iodine belong to the same group and

A.

are gaseous at room temperature.

B.

form white precipitate with AgNO3(aq)

C.

react violently with hydrogen without heating

D.

react with alkali

Correct answer is D

No explanation has been provided for this answer.