Chemistry questions and answers

Chemistry Questions and Answers

Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.

2,256.

Use the option above to answer this question. The structure of benzoic acid is

A.

A

B.

B

C.

C

D.

D

Correct answer is D

No explanation has been provided for this answer.

2,257.

The times taken for iodine to be liberated in the reaction between sodium thiosulphate and hydrochloric acid at various temperature are as follows. These results suggest that

A.

for a 10o rise in temperature, rate of reaction is double

B.

for a 10 o rise in temperature, rate of reaction is halved

C.

time taken for iodine to appear does not depend on temperature

D.

for a 10 o rise in temperature rate of reaction is tripled

Correct answer is B

The iodine liberation process is significantly affected by the amount of acid, that of potassium iodide added, the waiting time for the liberation, and light; therefore, the process plays a key role for the accuracy of the titration results.

for a 10 o rise in temperature, rate of reaction is halved

2,258.

Use the option above to answer this question. Which is the correct set of results for tests conducted respectively on fresh lime juice and ethanol.

A.

A

B.

B

C.

C

D.

D

Correct answer is A

lime juice reacts with NaCO3 with the evolution of CO2 because it is an acid while NaCO3 with ethanol does not result in a significant chemical reaction.

2,259.

Use the options above to answer this question. Which is the structural formula for pent-2-enoic acid?

A.

A

B.

B

C.

C

D.

D

Correct answer is C

No explanation has been provided for this answer.