Jamb Chemistry 1989 Past Questions and Answers

Question 26:

• JAMB 1989

Gunpower is made from charcoal, sulphur and potassium trioxonitrate (V) The salt in the mixture performs the function of

A. An oxidant
B. A reductant
C. A solvent
D. A catalyst

Question 27:

• JAMB 1989

Which of the following reactions is (are) feasible?
I Br ₍₁₎ + 2CI _2(aq) 2Br _(aq) + CI _2(g)
ll 21 _(aq) + Br ₂₍₁₎ 2Br _(aq) + 1 _2(s)
lll 2F _(aq) + CI _2(g) 2CI _(aq) + F _2(g) IV 2F _(aq) + Br ₂₍₁₎ 2Br _(aq) + F _2(g)

A. L
B. Ll
C. L and lll
D. Lll and lV

Question 28:

• JAMB 1989

Bleaching powder, CaOCI₂, H₂O, deteriorates on exposure to air because

A. It loses its water of crystallization
B. Atmospheric nitrogen displaces chlorine from it
C. Carbon (IV) oxide of the atmosphere displaceschlorine from it
D. Bleaching agents should be stored in solution

Question 29:

• JAMB 1989

The products of the thermal decomposition of ammonium trioxonitrate (V) are

A. NO ₂ and oxygen
B. NH₃ and oxygen
C. Nitrogen and water
D. N₂O and water

Question 30:

• JAMB 1989

The scale of a chemical balance is made of iron plate and coated with copper electrolytically because

A. Iron is less susceptible to corrosion than copper
B. Copper is twice as less susceptitible to corrosion as iron
C. Copper is less susceptible to corrosion than iron
D. Copper and iron are equally susceptible to corrosion