Rates of Chemical Reaction - Jamb Chemistry Past Questions and Answers

Question 76:

• JAMB 2018

In the preparation of oxygen by heating KCIO, in the presence of MnO\(_2\) only moderate heat is needed because the catalyst acts by \(_2\)

A. Lowering the pressure of the reaction
B. Increasing the surface area of the reaction
C. Increasing the rate of the reaction
D. Lowering the energy barrier of the reaction

Question 77:

• JAMB 2018

What is the concentration of a solution containing 2g of NaOH in 100cm3 of solution? [Na = 23, O =16, H = 1]

A. 0.40 moldm\(^{-3}\)
B. 0.50 moldm\(^{-3}\)
C. 0.05 moldm\(^{-3}\)
D. 0.30 moldm\(^{-3}\)

Question 78:

• JAMB 2018

2KClO3(g) MNO3→ 2KCl(s) + 3O2(g)
The importance of the catalyst in the reaction above is that

A. Heating may not be required before the reaction takes place
B. The reaction is controllable even at a high temperature
C. The reaction produces large quantity of oxygen
D. The reaction takes place more rapidly at a lower temperature

Question 79:

• JAMB 2018

The collision theory explains reaction rates in terms of

A. Size of the product
B. Frequency of collision of the reactants
C. Size of reactant
D. Frequency of collision of the products

Question 80:

• JAMB 2019

Consider the reaction
A\(_{(s)}\) + 2B\(_{(g)}\) → 2C\(_{(aq)}\) + D\(_{(g)}\)
What will be the effect of a decrease in pressure on the reaction?

A. The equilibrium will shift
B. Rate of forward reaction will increase
C. Rate of backward reaction will increase
D. Rates of forward and backward reaction are not affected