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.

2,126.

Which of the following correctly explains why iodine crystals change directly into the gaseous state when heated?

A.

lodine crystals sublime

B.

lodine atoms are held together by strong forces

C.

lodine molecules are held together by weak forces

D.

lodine molecules are covalent

E.

lodine is a solid at room temperature

Correct answer is C

No explanation has been provided for this answer.

2,127.

Aqueous sodium trioxocarbonate (IV) solution is alkaline because

A.

acid from which it is formed is strong

B.

sodium is an alkali metal

C.

sodium trioxocarbonate (IV) is decomposed by water

D.

sodium trioxocarbonate (lV) is stable to heat

E.

sodium triocarbonate (IV) is hydrolysed in water

Correct answer is E

No explanation has been provided for this answer.

2,128.

Which of the following equations represents the reaction of chlorine with hot concentrated sodium hydroxide solution?

A.

2KOH+CI2 → KCIO + KCI + H2O

B.

4KOH + 2CI → 4KCI + 2H2O + O2

C.

6KOH + 3CI2 → KCIO3 + 5KCI + 3H2O

D.

2KOH + CI2 → 2KCI + H2O2

E.

KOH + 2CI2 + H2O → KCI + 3HCI + O2

Correct answer is C

No explanation has been provided for this answer.

2,129.

Which of the following is not a naturally occurring iron ore?

A.

FeCl2

B.

Fe2O3O3

C.

Fe2O3

D.

FeCO3

E.

FeS2

Correct answer is A

No explanation has been provided for this answer.

2,130.

Which of the following metals cannot extracted from its ore by using carbon (ll) oxide as the reducing agent?

A.

Cu

B.

Zn

C.

Al

D.

Pb

E.

Fe

Correct answer is C

No explanation has been provided for this answer.