Rates of reaction test questions - WJEC - GCSE Chemistry (Single Science) Revision

1

What name is given to the minimum amount of energy needed by particles for them to react when they collide?

Activation energy

Catalytic energy

Threshold energy

2

What is the name of the model which is used to explain how different factors affect the rate of a reaction?

Particle theory

Big Bang theory

Collision theory

3

What piece of apparatus could be used to measure the volume of gas produced in a reaction?

Gas syringe

Beaker

Top pan balance

4

Which of the following would speed up a reaction?

Using lumps instead of powder

Increasing the concentration of an acid

Decreasing the temperature

5

When a dilute acid is added to sodium thiosulphate solution a precipitate of sulfur slowly forms. Which of the following measurements could be made to compare the rates of this reaction using different concentrations of acid?

Measure the time taken for a cross drawn under the beaker to disappear

Measure how the mass of beaker changes with time

Measure the time taken for the reaction to be completed

6

What type of substance must be produced by a reaction in order to measure the rate of reaction using the change in mass of the reaction?

Gas

Liquid

Solid

7

During a reaction between calcium carbonate and hydrochloric acid, the mass of the reaction decreases by 0.5 g over 20 minutes. What is the average rate of reaction?

0.025 g per minute

40 g per minute

0.5 g per minute

8

The reaction between dilute hydrochloric acid and sodium thiosulfate can be monitored using a light sensor and data logger. The reaction is considered to be finished when the light level falls to a constant level. How do you calculate the rate of reaction using this information?

Divide the final light level by the time taken for the light level to decrease to that level

Divide the time taken for the light level to stop decreasing by the change in light level

Divide the change in light level by the time taken for the light level to stop decreasing

9

Why is a digital thermometer more suitable to measure temperature rather than an analogue thermometer?

A digital thermometer is more accurate than an analogue thermometer

A digital thermometer has a higher resolution than an analogue thermometer

A digital thermometer has a lower resolution than an analogue thermometer

10

Gas syringes are generally better to measure the volume of gas produced than a measuring cylinder/gas jar. Which of the following statements reflect this?

There is no time delay in connecting the syringe

None of the gas escapes before connecting the gas syringe

A gas syringe has a precise scale, a measuring cylinder/gas jar does not