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.

3,606.

The property which makes alcohol soluble in water is the

A.

boiling point

B.

hydrogen bonding

C.

ionic character

D.

covalent nature

Correct answer is B

No explanation has been provided for this answer.

3,607.

The furring of kettles is caused by the presence in the water of?

A.

Calcium tetraoxosulphate (VI)

B.

Calcium hydrogentrioxocarbonate (IV)

C.

Calcium hydroxide

D.

Calcium trioxocarbonate (IV)

Correct answer is D

The furring of kettles or boilers - this is as a result of the decomposition of \(Ca(HCO_3)_2\) into \(CaCO_3\), and this\(CaCO_3\) coats the inside of a kettle or boiler used in heating water containing dissolved \(Ca(HCO_3)_2\).

3,608.

The substance least considered as a source of environmental pollution is

A.

Lead compounds

B.

Organophosphorous compounds

C.

Silicate minerals

D.

Uranium

Correct answer is C

No explanation has been provided for this answer.

3,609.

25cm3 of a 0.2 mol dm3 solution of Na2CO3 requires 20 cm3 of a solution of HCl for neutralization. The concentration of the HCl solution is

A.

0.5 mol dm3

B.

0.6 mol dm3

C.

0.2 mol dm3

D.

0.4 mol dm3

Correct answer is A

No explanation has been provided for this answer.

3,610.

Three drops of a 1.0 mol dm-3 solution of NaOH are added to 20 cm3 of a solution of pH 8.4. The pH of the resulting solution will?

A.

Close to that of pure water

B.

Unaltered

C.

Greater than 8.4

D.

Less than 8.4

Correct answer is C

A strong base is one that fully dissociates to give ions in solution. Weak bases only partially dissociate in a solution,

while the strong bases dissociate fully in a solution. Weak bases have pH 7.3 – 10, strong ones have pH 10 – 14.