JAMB Chemistry Past Questions & Answers - Page 207

1,031.

Oil spillage in ponds and creeks can be cleaned up by?

A.

burning off the oil layer

B.

spraying with detergent

C.

dispersal with compressed air

D.

spraying with hot water

Correct answer is B

No explanation has been provided for this answer.

1,032.

Which of the following water samples will have the highest titre value when titrated for the Ca2+ ions using soap solution?

A.

Permanently hard water after boiling

B.

temporarily hard water after boiling

C.

Rain water stored in a glass jar for two years

D.

Permanent hard water passed through permuitit

Correct answer is A

No explanation has been provided for this answer.

1,033.

In the purification of town water supply, alum is used principally to?

A.

kill bacteria

B.

control the pH of water

C.

improve the taste of the water

D.

coagulate small pasrticles of mud

Correct answer is D

No explanation has been provided for this answer.

1,034.

A stream of air was successively passed through three tubes X, Y and Z containing a concentrated aqueous solution of KOH, red hot copper powder and fused calcium chloride respectively. What was the composition of the gas emanating from tube Z?

A.

CO2 ad ithe inert gases

B.

N2, CO2 and the inert gases

C.

N2 and the inert gases

D.

water vapour, N2 and the inert gases

Correct answer is C

No explanation has been provided for this answer.

1,035.

The greater the different in electronegativity between bonded atoms, the?

A.

lower the polarity of the bond

B.

higher the polarity of the bond

C.

weaker the bond

D.

higher the possibility of the substance formed being a molecule

Correct answer is B

Bond polarity and ionic character increase with an increasing difference in electronegativity.

The electronegativity (χ) of an element is the relative ability of an atom to attract electrons to itself in a chemical compound and increases diagonally from the lower left of the periodic table to the upper right.