WAEC Chemistry Past Questions & Answers - Page 275

1,371.

CH4(g) + 2O2(g) → 2H2O(l) + CO2(g) ∆H = 890KJ mo-1 ∆H in the reaction represented by the equation above is the enthalpy of

A.

formation

B.

combustion

C.

solution

D.

activation

E.

neutralization

Correct answer is B

No explanation has been provided for this answer.

1,372.

A compound which liberates carbon (IV) oxide from a hydrogentrioxocarbonate (lV) could have the molecular formula

A.

C2H5OH

B.

C 3H 4

C.

HCOOH

D.

H2O2

E.

C6H6

Correct answer is C

No explanation has been provided for this answer.

1,373.

In which of the following are the substances arranged in their correct order of increasing melting point?

A.

Sodium chloride, sulphur, diamond

B.

Diamond, sodium chloride, sulphur

C.

Sulphur, sodium chloride, diamond

D.

Diamond, sulphur, sodium chloride

E.

Sulphur, diamond, sodium chloride

Correct answer is C

No explanation has been provided for this answer.

1,374.

Which of the following statements is not correct? Group 7 elements

A.

are diatomic

B.

are good oxidizing agents

C.

are highly electronegative

D.

have relatively low ionization potentials

E.

have high electron affinity

Correct answer is D

No explanation has been provided for this answer.

1,375.

Which of the following modes of motion is exhibited by the particles of a solid?

A.

Vibrational and random motion

B.

Vibrational and translational motion

C.

Translational and random motion

D.

Vibrational motion only

E.

Translational motion only

Correct answer is D

The cohesive forces binding the particles of a solid are strong enough to restrict their movement so that they are held together in a fixed point. They only vibrate and rotate about their fixed point.