A student adds marble chips to hydrochloric acid and collects the carbon dioxide in a gas syringe.
Table of gas volume against time: 0 seconds 0, 10 seconds 22, 20 seconds 38, 30 seconds 50, 40 seconds 56, 50 seconds 60, 60 seconds 60 cubic centimetres.
Time in s
0
10
20
30
40
50
60
Volume in cm³
0
22
38
50
56
60
60
.1
Calculate the mean rate of reaction in the first 30 seconds.
[2 marks]
.2
Give the earliest time in the table by which the reaction had stopped.
[1 mark]
.3
Describe how the rate changes during the reaction.
[1 mark]
2 marksFoundation
Spec and skills
Original practice question
Answer and supported method checks
Dry air is a mixture of gases.
.1
Which gas makes up about four-fifths of the air?
[1 mark]
.2
A classroom holds 200 m³ of air. Calculate the approximate volume of oxygen in the room, using oxygen as one-fifth of the air.
[1 mark]
3 marksFoundation
Spec and skills
Original practice question
Answer and supported method checks
Crude oil is a mixture of hydrocarbons.
.1
Define the term hydrocarbon.
[1 mark]
.2
Butane has 4 carbon atoms. Write the formula of butane.
[1 mark]
.3
Which fraction is used as fuel for aircraft?
[1 mark]
4 marksFoundation
Spec and skills
Original practice question
Answer and supported method checks
A teacher adds a small piece of lithium to a trough of water containing universal indicator.
.1
Give two observations the students would see.
[2 marks]
.2
Complete the word equation: lithium + water → lithium hydroxide + ______
[1 mark]
.3
The teacher repeats the demonstration with potassium. Predict how the reaction compares.
[1 mark]
3 marksFoundation
Spec and skills
Original practice question
Answer and supported method checks
A student adds small pieces of four metals to dilute hydrochloric acid and to water.
Table: metal A reacts vigorously with acid and slowly with water; metal B reacts slowly with acid and not with water; metal C does not react with either; metal D reacts vigorously with water.
Metal
With dilute acid
With water
A
Vigorous fizzing
Slow bubbles
B
Slow bubbles
No reaction
C
No reaction
No reaction
D
Too dangerous to try
Vigorous fizzing, melts
.1
Use the results to put the metals in order of reactivity, most reactive first.
[1 mark]
.2
Which metal could be copper?
[1 mark]
.3
Complete the word equation: magnesium + hydrochloric acid → magnesium chloride + ______
