Jamb Chemistry Past Questions and Answers

Question 361:

• JAMB 1984

Naphthalene when heated melts at 354 K (81 ^oC). At this temperature the molecules of naphthalene

A. Decompose into smaller molecules
B. Change their shape
C. Are oxidized by atmospheric oxygen
D. Contract
E. Become mobile as the inter molecular forces are broken

Question 362:

• JAMB 1984

The ratio of the number of molecules in 2g of hydrogen to that in 16g of oxygen is

A. 2:1
B. 1:1
C. 1:2
D. 1:4
E. 1:8

Question 363:

• JAMB 1984

The balanced equation for the reaction of tetraoxosulphate(VI)acid with aluminium hydroxide to give water and aluminium tetraoxosulphate(VI) is

A. H₂SO₄ + Al(OH)₂ \(\to\) 2H₂O + AlSO₄
B. 3H₂SO₄ + 2Al(OH)₃ \(\to\) 6H₂O + Al₂(SO₄)₃
C. 3H₂SO₄ + 2AlH \(\to\) 6H₂O + Al(SO₄)₃
D. 3H₂ SO₄ + 2Al(OH)₃ \(\to\) Al(SO₄)₃
E. H₂SO₄ + Al(OH)₃ \(\to\) H₂O + Al₂(SO₄)₃

Question 364:

• JAMB 1984

Which of the following mixtures would result in a solution of pH greater than 7?

A. 25.00 cm³ of 0.05 M H₂SO₄ and 25.00cm³ of 0.50 M Na₂CO₃
B. 25.00 cm³ of 0.05 M H₂SO₄ and 25.00 cm³ of 0.10 M NaHCO₃
C. 25.00 cm³ of 0.11 MH₂SO₄ and 25.00cm³ 0. 10 M NaOH
D. 25.00cm³ of 0.11 MH₂ SO₄ and 50.00 cm³ of 0.05 M NaOH
E. 25.00cm³ of 0.25 M H₂SO₄ and 50.00cm³ of 0.20 M NaOH

Question 365:

• JAMB 1984

In which of the following reactions does hydrogen peroxide act as a reducing agent?

A. H₂S + H₂O₂ \(\to\) S + 2H₂O
B. PbSO₃ + H₂O₂ \(\to\) PbSO₄ + H₂O
C. 2I+ 2H⁺ + H₂O₂ \(\to\) I₂ + 2H₂O
D. PbO₂ + 2HNO₃ + H₂O₂ \(\to\) Pb(NO₃)₂ + 2H₂O + O₂
E. SO₂ + H₂O₂ \(\to\) H₂SO₄