Jamb Chemistry 1999 Past Questions and Answers

Question 31:

• JAMB 1999

The salt that reacts with dilute hydrochloric acid to produce a pungent smelling gas which decolourizes acidified purple potassium tetraoxomanganate (VII) solution is

A. Na₂SO₄
B. Na₂SO₃
C. Na₂S
D. Na₂CO₃

Question 32:

• JAMB 1999

A pair of compounds that can be used to generate a gas which has physiological effect on human beings is

A. Sodium trioxonitrate (V) and calcium chloride
B. Sodium dioxonitrate (III) and ammonium chloride
C. Sodium trioxonitrate (V) and ammonium chloride
D. Sodium dioxonitrate (III) and potassium chloride

Question 33:

• JAMB 1999

Hydrogen is used in oxy-hydrogen flames for melting metals because it

A. Evolves a lot of heat when burnt
B. Combines explosively with oxygen
C. Is a very light gas
D. Is a rocket fuel

Question 34:

• JAMB 1999

What properties of duralumin make it more useful than its constituent metals?

A. It is heavy with a high melting point
B. It is malleable and has high density
C. It is strong and light
D. It is hard and ductile

Question 35:

• JAMB 1999

The pair of metals in the reactivity series that are usually extracted by the electrolysis of their ores is

A. Magnesium and zinc
B. Magnesium and calcium
C. Copper and zinc
D. Lead and calcium