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.

2,277.

The i.u.p.A.C name for the compound

A.

2-chloro-isopentane

B.

3-chloro-isopentane

C.

2-chloro-2-methylbutane

D.

1-chloro-2,2- dimethylpropane

E.

2-chloro-2-ethylpropane

Correct answer is C

No explanation has been provided for this answer.

2,278.

The solubility curve of a solid X (molecular mass = 160) is as show above. 1,000 cm3 of a saturated solution of X at 80°C is cooled to 40°C . The weight of X crystalized out would be

A.

10 g

B.

12 g

C.

14 g

D.

16 g

E.

18 g

Correct answer is D

At 80°C, we have \(1000cm^{3} = 0.4mol/cm^{3}\)

40°C = \(0.3mol/cm^{3}\)

hence, the loss in concentration = \(0.1mol/cm^{3}\)

= \(0.1 \times 160 = 16g\)

2,279.

The IUPAC name for

A.

1-methlpentan

B.

3-methylbutane

C.

2-methylbutane

D.

1-dimethylpropane

E.

2-methylpentane

Correct answer is C

No explanation has been provided for this answer.

2,280.

Copper sulphate solution was electrolysed using the apparatus show above. Which of the following changes are observed?

A.

The bulb lights and copper is deposited at both electrodes

B.

the bulb lights and copper is deposited at the anode and disappears from the cathode

C.

the bulb lights and copper is deposited at the cathode and oxygen liberated at the anode

D.

the bulb lights and copper is deposited at the cathode and disappears from the anode

E.

the bulb lights but no additional changes are observed

Correct answer is D

No explanation has been provided for this answer.