NECO Chemistry Past Questions & Answers - Page 12

56.

Which of these is NOT a physical property f water?

A.

Can be used to dissolve organic substances

B.

Has a boiling point of 100 ° C

C.

Has a density of 19cm3 at 40 °C

D.

Has a freezing point of 0 ° C

E.

is neutral to litmus

Correct answer is A

No explanation has been provided for this answer.

57.

The following gases are diatomic EXCEPT

A.

Fluorine

B.

Helium

C.

Hydrogen

D.

Nitrogen

E.

Oxygen

Correct answer is B

No explanation has been provided for this answer.

58.

If two elements X and Z with electronic configurations 2,8.3 and2,8,6 respectively combine, the compound formed will have the formula

A.

XZ

B.

XZ2

C.

X2Z

D.

X2Z3

E.

X3Z2

Correct answer is D

No explanation has been provided for this answer.

59.

The reaction of hydrochloric acid and calcium trioxocarbonate (IV) produces

A.

calcium chloride, carbon (IV) oxide and water

B.

calcium chloride, and trioxocarbonate (IV) acid

C.

calcium hydroxide, carbon (IV) oxide and chlorine gas

D.

calcium hydroxide, carbon (IV) oxide and water

E.

calcium metal and water.

Correct answer is A

No explanation has been provided for this answer.

60.

Brownian motion explains

A.

Boyle’s law

B.

Collision theory

C.

Laws of chemical combination

D.

Molecular motion in liquids and gases

E.

Vibrational motion in liquids.

Correct answer is D

No explanation has been provided for this answer.