The document discusses the key concepts related to the rate of a chemical reaction: 1. The rate of reaction is affected by factors like concentration, temperature, surface area, and presence of a catalyst. A catalyst increases the rate by lowering the activation energy without being consumed in the reaction. 2. Collision theory states that molecules must collide with sufficient energy, called the activation energy, for a reaction to take place. Increasing effective collisions through factors like concentration and temperature increases the rate. 3. A catalyst facilitates the reaction by providing an alternative reaction pathway with lower activation energy, allowing more particles to react per unit time and increasing the rate.

1. RATE OF REACTION
1.
The collisions that are successful in producing a chemical reaction are called
A
effective collisions
B
ineffective collisions
C
successful collisions
D
unsuccessful collisions
2.
The figure shows the energy profile of a reaction.
Which of the following options A, B, C, and D in the figure shows the activation energy?
Energy
Reactants
B
C
Products
A
D
Reaction path
3.
Which of the following alters the rate of a chemical reaction but remains chemically unchanged at
the end of a reaction?
A
Product
B
Catalyst
C
Reactant
4.
The number of collisions per second that will result in a reaction is known as collision theory
A
effective collision
B
effective collision frequency
C
ineffective collision frequency
5.
Which of the following equations gives the meaning of rate of reaction?
A
B
Increase in mass of reactant
time taken
C
Decrease in mass of reactant
Volume of gas liberated
D
6.
Volume of gas liberated
time taken
Volume of gas liberated
Changes in the mass of reactant
Which of the following statement is true about the collision theory?

2. A
B
C
D
7.
All collisions produce a reaction.
The increase in the activation energy will increase the rate of reaction.
The increase in the effective collision frequency will increase the rate of reaction.
The increase in the effective collision frequency will increase the quantity of the product
formed.
Which of the following does not affect the rate of a reaction?
A
Temperature
B
Size of a reactant
C
Volume of solution
D
Concentration of solution
8.
Which of the following is not the characteristic of catalyst?
A
Are specific in their actions.
B
Increase the quantity of products.
C
Do not change chemically after a reaction.
D
Are required in small amount to affect the rate of reaction.
9.
The equation shows the reaction between calcium carbonate and dilute hydrochloric acid.
CaCO3 (s) + 2HCl (aq)
CaCl2 (aq) + H2O (l) + CO2 (g)
After 60 seconds, the volume of gas produced is 85 cm 3. Calculate the average rate of reaction in
the unit of cm3s-1.
A
0.71
B
1.42
C
25.00
D
5100.00
10.
When the concentration of a solution increases, the rate of reaction also increases.
Which of the following solutions will produce the highest rate of reaction between magnesium and
dilute hydrochloric acid?
A
50 cm3 of 0.10 moldm-3 HCl
B
50 cm3 of 0.15 moldm-3 HCl
C
50 cm3 of 0.20 moldm-3 HCl
D
50 cm3 of 0.25 moldm-3 HCl
11.
Which of the following is true?
Catalyst
Process
A
Iron
Ostwald process for producing nitric acid
B
Vanadium(V) oxide Contact process for producing sulphuric acid
C
Platinum
Haber process for producing ammonia
D
Nickel
Cracking process for producing alkane and alkene.
12.
Which of the following has the highest rate of reaction?
A
B
C
D
Reaction
Combustion of magnesium in oxygen
Photosynthesis
Fermentation
Rusting of iron
2
Time taken
30 seconds
1 day
2 days
3 days

3. 13.
Which of the following is incorrect about rate of reaction?
A
An increased in pressure decreases the rate of reaction.
B
The smaller the size of the solid particles, the higher the rate of reaction.
C
The higher the concentration of the reactant, the higher the rate of reaction.
D
The rate of reaction increases if the temperature of the reactants is increased.
14.
Which of the following reactions will be affected by the changes in pressure?
A
2H2O2 (aq) → 2H2O (l) + O2 (g)
B
N2 (g) + 3H2 (g)
2NH3 (g)
C
Mg (s) + 2HCl (aq) → MgCl2 (aq) + H2 (g)
D
CaCO3 (s) + 2HCl (aq) → CaCl2 + H2O (l) + CO2 (g)
15.
Sulphur is precipitated when sodium thiosulphate solution is added with dilute hydrochloric acid in
a conical flask. The rate of precipitation of sulphur can be increased by
A
using a bigger conical flask.
B
stirring the reaction mixture.
C
heating the reaction mixture.
D
adding water to increase the volume of mixture.
16.
Why is food cut into small pieces before cooking
A
The food can be stirred easily.
B
The total pieces of food are more.
C
The total surface area of the food is larger.
D
The food can be cooked at a higher temperature.
17.
The equation shows the reaction between calcium carbonate and dilute hydrochloric acid.
CaCO3 + 2HCl → CaCl2 + CO2 + H2O
Based on the equation, which one of the following changes can be used to determine the rate of
reactions in the above reaction?
A
Increase in the mass of calcium carbonate.
B
Increase in the concentration of hydrochloric acid.
C
Decrease in the concentrarion of calcium chloride.
D
Increase in the volume of carbon dioxide is produced.
18.
The equation shows the reaction to produce hydrogen gas.
H2SO4 + Zn → ZnSO4 + H2
Which of the following would increase the rate of production of hydrogen gas?
A
Increase the volume of acid.
B
Increase the size of zinc granules.
C
Increase the atmospheric pressure.
D
Increase the temperature of the mixture.
The graph shows the volume of carbon dioxide gas produced against time when calcium
carbonate is added to dilute hydrochloric acid.
19.
Volume of CO2/cm3
3

4. Time/s
Which of the following statement explains the change in the gradient of the curve?
A
The temperature of the mixture decreases with time.
B
The concentration of hydrochloric acid decreases with time.
C
The total surface area of calcium carbonate increases with time.
D
The concentration of calcium chloride formed increases with time.
20.
The graph shows the volume of carbon dioxide produced at room conditions when 1 g of calcium
carbonate reacts with excess hydrochloric acid.
Volume of CO2/cm3
Time/s
Calculate the overall rate of this reaction.
A
6 cm3s-1
B
4 cm3s-1
C
3 cm3s-1
D
2 cm3s-1
21.
The reaction between hydrochloric acid and zinc produces hydrogen gas. In an experiment, a
maximum volume of 48.0 cm3 of hydrogen gas is produced in 120 s.
What is the average rate of the reaction?
A
0.2 cm3s-1
B
0.4 cm3s-1
C
1.8 cm3s-1
D
2.5 cm3s-1
22.
The table shows the total volume of gas collected at regular intervals in a reaction.
Time(s)
0 30 60 90 120 150 180 210
Volume of gas(cm3) 0.0 4.0 7.4 10.4 12.8 14.6 17.2 17.2
What is the average rate of reaction in the second minute?
A
0.080 cm3s-1
B
0.090 cm3s-1
C
0.107 cm3s-1
D
0.133 cm3s-1
4

5. 23.
Three experiments are conducted to compare the rate of a reaction. The results of the experiments
are shown below:
Experiment
Reactants
Rate of reaction
2 g of magnesium ribbon with 10 cm3 of 1.0
p
moldm-3 hydrochloric acid.
2 g of magnesium ribbon with 10 cm3 of 2.0
II
q
moldm-3 hydrochloric acid.
2 g of powdered magnesium with 10 cm 3 of 2.0
III
r
moldm-3 hydrochloric acid.
Arrange the rate of reaction for the three experiments according to increasing order.
A
p, q, r
B
r, p, q
C
r, q, p
D
q, r, p
I
24.
The table shows the results for two experiments.
Experiment
1
2
Time taken to collect
60 cm3 of H2(s)
Reactants
1.0 g of magnesium ribbon and 50 cm3
of 1.0 moldm-3 sulphuric acid
1.0 g of magnesium powder and 50 cm3
of 1.0 moldm-3 sulphuric acid
30
10
Based on the results, state the relationship between the sizes of solid particles with the rate of
reaction.
…………………………………………………………………………………………………………………
………………………………………………………………………………………………………………
The graph shows the effect of adding copper(II) sulphate,CuSO 4 solution to the reaction between
zinc and hydrochloric acid. In this reaction, CuSO 4 solution is used as a catalyst.
Volume of H2/cm3
25.
With CuSO4 solution
Based on the graph,
Without
CuSO4
solution
state two
characteristics of a catalyst.
………………………………………………….........................................................................................
Time/s
.............................................................................................................................................................
26.
The figure shows the progress of a chemical reaction.
5

6. Time(s)
Progress of reaction
particle of
reactant.
particle of
product.
0
5
10
15
20
Based on the figure, describe what happens to the amount of reactant and the amount of product
as the chemical reaction progresses.
……………………………………………………………...
…………………………………………………………..............................................................................
..............................
.........................................................................................................................................
Catalysts are usually used to increase the rate of industrial processes.
These enable the processes to be completed in a shorter time, at a lower
temperature and pressure. Hence the cost of production will be reduced.
27.
Which of the followings are the reasons for the use of catalysts in industrial processes?
I.
To reduce the cost of production.
II. Enables the processes to be completed in a shorter time.
III. Enables the processes to be carried out at a higher pressure.
IV. Enables the processes to be carried out at a higher temperature.
A
B
I and II only
I and IV only
C
D
II and III only
III and IV only
The presence of catalyst in a chemical reaction allows the reaction to take place
through an alternative path which requires lower activation energy. Thus more
colliding particles are able to achieve the lower activation energy. The frequency
of effective collision increases and hence the rate of reaction is higher.
28.
The use of a catalyst can increase the rate of a reaction, this is because
A
a catalyst reduces the activation energy.
B
a catalyst increases the activation energy.
C
a catalyst reduces the number of collision.
D
a catalyst increases the number of collision.
When a small amount of manganese (IV) oxide is added to hydrogen peroxide.
Hydrogen peroxide decomposes rapidly to produce oxygen gas. Manganese
(IV) oxide acts as a catalyst to increase the rate of decomposition of hydrogen
peroxide.
30
What is the gas produced when hydrogen peroxide decomposes?
A
Oxygen
C Carbon dioxide
B
Hydrogen
D Nitrogen dioxide
6

7. 31
What is the function of manganese (IV) oxide?
A
To increase the volume of oxygen gas.
B
To decrease the volume of oxygen gas.
C
To change the chemical properties of hydrogen peroxide.
D
To increase the rate of decomposition of hydrogen peroxide
7