JAMB Chemistry Past Questions & Answers - Page 346

1,726.

What is the IUPAC nomenclature of the compound NaCIO?

A.

sodium oxochlorate (I)

B.

sodium chloro (I) oxide

C.

sodium monooxochlorate (II)

D.

sodium chloro (I) monoxide

Correct answer is A

NaClO is sodium oxochlorate(I) in IUPAC nomenclature

1,727.

The oxidation state of carbon in HCOOH is

A.

-1

B.

+2

C.

+3

D.

zero

Correct answer is B

HCOOH
O.N of H + O.N of C + 2* O.N of oxygen of
H = 0
1 + X + 2X - 2 + 1 = 0
2 + X -4 = 0
X = 4 - 2 = +2

1,728.

Insoluble salts can be prepared by?

A.

titrating an alkali against an appropriate acid

B.

reacting an acid with trioxocarbonate (IV) salt

C.

directing combination of the elements which make up the salt

D.

mixing two soluble compounds containing the metallic radical and the acidic radic

Correct answer is D

An insoluble salt can be prepared by a precipitation method through a double decomposition reaction.

Two soluble metal salts react with each other to form one soluble salt and one insoluble salt .

Lead nitrate solution and sodium chloride solution react to produce solid lead chloride , leaving soluble sodium nitrate in solution.

The lead chloride can be recovered by filtration.

1,729.

0.05 mol dm-3 HCl is neutralized by 25 cm3 NaOH. If the volume of acid used is 32.00cm3, what is the concentration of the base

A.

0.016 mol dm-3

B.

0.032 mol dm-3

C.

0.039 mol dm-3

D.

0.064 mol dm-3

Correct answer is D

HCl + NaOH → NaCl + H2O
CAVA = NA/NB = (0.05 * 32)/(CB * 25)
∴ CB = (0.05 * 32)/25 = 0.064 mol dm-3

1,730.

The basicity of CH3COOH is

A.

1

B.

2

C.

3

D.

4

Correct answer is A

The basicity of CH3COOH is 1. Which means it has just one ionizable ion.