Higher Chemistry
Unit 1
Section 1 Reaction Rates
Multiple Choice Questions
This is designed to be used by teachers to help students develop
skills in answering multiple choice questions.
Douglas Racey, Waid Academy, Anstruther, Fife, Scotland
Higher Chemistry
1.
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
Excess marble chips (calcium carbonate)
were added to 25cm3 of hydrochloric acid,
concentration 2 mol l-1. Which measurement,
taken at regular intervals and plotted against
time, would give the graph shown?
A.
B.
C.
D.
temperature
volume of gas produced
pH of solution
mass of the beaker and contents
Answer
D.
Higher Chemistry
2.
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
The same reaction was carried out at four different
temperatures and the times taken for the reaction recorded.
Temperature /oC
20
30
40
50
Time / s
60
30
14
5
The results show that
A. a small rise in temperature results in a large increase in reaction
rate
B. the activation energy increases with increasing temperature
C. the rate of the reaction is directly proportional to the
temperature
D. the reaction is endothermic
Answer
A.
Higher Chemistry
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
3.
In area X
A. molecules always form an activated complex
B. no molecules have the energy to form an activated complex
C. collisions between molecules are always successful in forming
products
D. all molecules have the energy to form an activated complex
Answer
D.
Higher Chemistry
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
4. Excess zinc was added to 100cm3 of
hydrochloric acid,
concentration 1 mol l-1 Graph I
refers to this reaction.
Graph II could be for
A. excess zinc reacting with 100cm3 hydrochloric acid, concentration 2 mol l-1
B. excess zinc reacting with 100cm3 of sulphuric acid, concentration 1 mol l-1
C. excess zinc reacting with 100cm3 of ethanoic acid, concentration 1 mol l-1
D. excess magnesium reacting with 100cm3 of hydrochloric acid,
concentration 1 mol l-1
Answer
D.
Higher Chemistry
5.
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
When copper carbonate reacts with excess acid,
carbon dioxide is produced.
The curves shown were obtained
under different conditions.
The change P to Q could be brought about by
A. increasing the concentration of the acid
B. decreasing the mass of copper carbonate
C. decreasing the particle size of the copper carbonate
D. adding a catalyst
Answer
B.
Higher Chemistry
6.
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
The continuous use of large extractor fans greatly
reduces the possibility of an explosion in a flour
mill because
A.
a build up in the concentration of oxygen
is prevented
B.
local temperature rises a prevented by the
movement of air
C.
particles of flour suspended in the air are
removed
D.
the slow accumulation of carbon monoxide is
prevented
Answer
C.
Higher Chemistry
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
7. A small increase in temperature results in a
large increase in reaction rate .
The main reason for this is that
A.
more collisions are taking place
B.
the enthalpy change is lowered
C.
the activation energy is lowered
D.
many more particles have energy greater
than the activation energy.
Answer
D.
Higher Chemistry
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
8. The graph shown below shows the variation
of concentration of a reactant with time as a
reaction proceeds.
The average reaction rate, in mol l-1 s-1,
during the first 20s is
A.
0.0025
B.
0.0036
C.
0.0075
D.
0.0090
Answer
C.
Higher Chemistry
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
9. Which of the following is not a correct
statement about the effect of a catalyst?
The catalyst
A.
lowers the energy which molecules need for
successful collision
B.
C.
D.
provides an alternative route to the products
forms weak bonds with reacting molecules
provides energy so that more molecules have
successful collisions.
Answer
D.
Higher Chemistry
Unit 1 - Section 1 Reaction Rates
Multiple Choice Questions
10. For any chemical reaction, the temperature is
a measure of
A.
the average kinetic energy of the molecules
which react
B.
C.
D.
the average kinetic energy of all the molecules
the activation energy
the minimum kinetic energy required before
reaction occurs
Answer
B.