WAEC Chemistry Past Questions & Answers - Page 137

681.

Which of the following statements about displacement reaction is correct?

A.

A more electropositive element displaces a less electroposive one

B.

A less electropositive element displaces a more electropositive one

C.

The position of elements in the reactivity series has no effect on the reaction

D.

it only occurs when the reaction is at equilibrium

Correct answer is A

No explanation has been provided for this answer.

682.

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.

683.

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.

684.

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.

685.

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.