Essential Chemistry for IGCSE - Rate Of Reaction (Section 3)
1
A student is investigating the rate of reaction between magnesium and hydrochloric acid. Which of the following would be a valid method for measuring the rate of reaction?
Answer
(D)
All of the above.
2
What is the effect of increasing the concentration of reactants on the number of collisions?
Answer
(A)
Increases collisions
3
What is the function of an inhibitor?
Answer
(B)
To slow down the reaction.
4
What does the term 'rate constant' (k) signify in the context of chemical kinetics?
Answer
(B)
The rate of the reaction at a specific temperature.
5
What is a common method for following the progress of a reaction that produces a gas?
Answer
(B)
Measuring the change in the volume of the gas produced.
6
Which of the following would decrease the rate of a chemical reaction?
Answer
(D)
Decreasing the surface area of the reactants.
7
What is the purpose of a catalyst in a chemical reaction?
Answer
(B)
To lower the activation energy and speed up the reaction.
8
What is the impact of a catalyst on the activation energy and rate of the reaction?
Answer
(C)
Decreases activation energy, increases the rate.
9
What is the effect on the rate of reaction if you add an inhibitor?
Answer
(B)
The rate of the reaction decreases.
10
What does a catalyst primarily do to affect the rate of a reaction?
Answer
(B)
Provides an alternative reaction pathway with a lower activation energy.
11
Which of the following is an example of an inhibitor?
Answer
(C)
A substance that slows down a reaction
12
What is activation energy?
Answer
(B)
The energy required for a reaction to occur.
13
If a catalyst is present in a reaction, what is a change that may be observed in the energy profile?
Answer
(B)
The activation energy will decrease.
14
If the rate of a reaction is proportional to the concentration of the reactant, what is the order of the reaction?
Answer
(B)
First order
15
In a reaction rate experiment, which of the following would be a good example of a control?
Answer
(C)
A reaction with no catalyst added.
16
Which of the following best describes the effect of surface area on the rate of reaction?
Answer
(A)
Increasing the surface area increases the rate of reaction.
17
What is the impact of an inhibitor on the rate of a reaction?
Answer
(B)
Decreases the rate of reaction.
18
How does increasing the concentration of reactants generally affect the rate of reaction?
Answer
(A)
It increases the rate of reaction.
19
What happens to the rate of reaction if you add a catalyst?
Answer
(A)
It increases the rate.
20
Which of the following factors will increase the rate of a reaction?
Answer
A
B
C
21
Which of the following is NOT a way to measure the rate of a chemical reaction?
Answer
(C)
Measuring the change in temperature.
22
How does a catalyst work?
Answer
(B)
By providing an alternate reaction pathway with lower activation energy.
23
How does the increase in temperature affect the kinetic energy of reactant particles?
Answer
(C)
It increases the kinetic energy.
24
If a reaction has a high activation energy, what does this imply?
Answer
(C)
The reaction will require a high temperature to proceed.
25
Which of the following is NOT mentioned as a way to follow the progress of a reaction?
Answer
(B)
Measuring the change in mass
26
How does a catalyst provide an alternate reaction pathway?
Answer
(B)
By providing an alternate reaction pathway with lower activation energy.
27
If a reaction is carried out using a powdered solid instead of a single large piece of the solid, what is the most likely effect on the reaction rate?
Answer
(C)
The rate increases.
28
What is the relationship between the surface area of reactants and the rate of reaction?
Answer
(C)
As surface area increases, the rate of reaction increases.
29
What is the relationship between concentration of a reactant and the reaction rate, according to the collision theory?
Answer
(C)
Increased concentration increases the reaction rate because more collisions occur.
30
Which of the following is NOT a factor that affects the rate of a chemical reaction?
Answer
(D)
The volume of the reactants
31
What is the effect of using smaller particles on the surface area of a reactant?
Answer
(C)
It increases the surface area.
32
If a reaction produces a gas, which of the following is a reliable method for monitoring its rate?
Answer
(C)
Measuring the decrease in mass.
33
What type of reaction is more likely to be successful if you need to make a fire?
Answer
(B)
Small pieces of wood burning with a large surface area
34
How can the rate of reaction be determined?
Answer
B
C
D
35
What happens to the rate of a reaction when a catalyst is added?
Answer
(B)
The reaction speeds up.
36
What is the most important factor that influences the rate of a chemical reaction?
Answer
(B)
The temperature of the reaction
37
What is the effect of a catalyst on the activation energy?
Answer
(C)
It decreases the activation energy.
38
What effect does increasing the temperature have on the rate of reaction?
Answer
(C)
It increases the rate.
39
What is the role of a light sensor in the context of reaction rates?
Answer
(B)
To measure the amount of light passing through a solution.
40
How is the rate of reaction generally determined?
Answer
(A)
By measuring how fast the reactants are used up or how fast the products are formed.
41
What is the relationship between concentration and the rate of a reaction?
Answer
(C)
Increasing concentration increases the reaction rate.
42
How does increasing the temperature affect the number of collisions between reacting particles?
Answer
(C)
It increases the number of collisions.
43
Which of the following methods can be used to measure the rate of reaction of a gas evolving reaction?
Answer
A
B
44
What are the factors that influence the rate of a reaction?
Answer
A
B
C
45
In the study of reaction rates, which factor is directly related to the number of successful collisions between reactant molecules?
Answer
(B)
The temperature of the reaction.
46
Which of the following factors can affect the rate of reaction?
Answer
A
B
C
47
Which of the following is a good method to measure the rate of a reaction that produces a gas?
Answer
(A)
Measuring the change in mass.
48
What are the key factors that affect the reaction rate?
Answer
(C)
The amount of catalyst added and the temperature of reaction
49
In the context of surface area and reaction rates, what is the effect of using smaller particles (e.g., powder) compared to larger pieces of the same reactant?
Answer
(C)
Smaller particles increase the rate of reaction.
50
If a reaction's rate is represented by a graph, what is the significance of a steeper slope?
