JAMB Chemistry Past Questions & Answers - Page 237

1,181.

Which of the following is NOT a redox reaction?

A.

2HNO2 + 2HI → 2H2O + 2NO + I2

B.

Zn + H2SO4 → ZnSO4 + H2

C.

Ca(HCO3)2 → CaCO3 + H2O + CO2

D.

4FeO + O2 → 2Fe2O3

E.

2Na + Cl2 → 2NaCl

Correct answer is C

Ca(HCO2) → CaCO3 + H2O + CO2 is not a redox reaction

1,182.

Which of the following combinations of conditions may increase the rate of a chemical reaction?

A.

Decrease in temperature, increase in concentration of the reactants

B.

Increase in temperature, addition of a catalyst, decrease in the surface area of the reactants

C.

Increase in temperature, increase in concentration, addition of a catalyst and increase in the surface area of the reactants

D.

Decrease in temperature concentration and surface area of the reactants

E.

Additionof a catalyst and in the absence of light

Correct answer is C

Increase in temperature, increase in concentration, increase the rate of chemical reaction

1,183.

What weight of sodium hydroxide is required to make 500 cm3 of 0.2 M solution?

(Na = 23, O = 16, H = 1)

A.

40 g

B.

20 g

C.

10 g

D.

4 g

E.

2 g

Correct answer is D

No explanation has been provided for this answer.

1,184.