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.

2,196.

In the experiment above, X could be a solution of

A.

sodium trioxonitrate (V) and ammonium chloride

B.

sodium trioxonitrate (lll) and ammonium chloride

C.

lead (ll) trioxonitrate (V) and copper turnings

D.

potassium trioxonitrate (V) and copper turnings

Correct answer is B

Nitrogen is prepared in the laboratory by heating an equimolar aqueous solution of ammonium chloride and sodium nitrite. The ammonium nitrite formed as a result of a double decomposition reaction, decomposes to form nitrogen gas.

\(NH_4Cl_{(aq)}+NaNO_{2(aq)} → NH_4NO_{2(aq)}+NaCl_{(aq)}\)

\(NH_4NO_{2(aq)} →N_{2(g)}  +2H_2O_{(l)}\).

 

 

(source: understanding chemistry by G O Ojukuku)

2,197.

In the diagram above , the activation energy for the backward reaction is

A.

+5kJ

B.

+15KJ

C.

+25KJ

D.

+30KJ

Correct answer is C

For the backward reaction, the activation energy = 40kJ - 15kJ = +25kJ

2,198.

The diagram above represents an atom that can combine with chlorine to form

A.

a covalent bond

B.

an electrovalent bond

C.

a hydrogen bond

D.

a co-ordinate bond

Correct answer is B

No explanation has been provided for this answer.

2,199.

The compound above is the product of the oxidation of

A.

2-methlbutan-2-ol

B.

2-methylbutan -1- ol

C.

2, 3-dimethylprop 1-ol

D.

Pentan -2- ol

Correct answer is B

No explanation has been provided for this answer.

2,200.

The compound above contains

A.

Sp 3 hybridized carbon atoms only

B.

Sp 2 hybridized carbon atoms only

C.

Sp 3 and Sp hybirdized carbon atoms

D.

Sp 3 and Sp 2

Correct answer is D

No explanation has been provided for this answer.