OCR GCSE Combined Science B (21st Century) Paper 4 June 2022 question paper

9 questions

Report a problem

The energy needs of the UK are met by a wide range of energy resources.

(a)

Which two energy resources are burned for heating?

Tick (✓) two boxes.

$Question 1, shown as an image$

[2]

Answer

(b)

Complete the sentences to describe how fossil fuel power stations generate electricity.

Use words from the list.

You can use each word once, more than once or not at all.

gas hydroelectric transformer turbine water wind

In coal and........ power stations........ is heated to produce

steam. The steam turns a........ which makes a generator rotate.

[3]

Answer

(c)

The table compares the ways in which the main energy resources are used to generate electricity.

For each row, tick (✓) all the statements that are true about the method used to generate electricity from each energy resource in the table.

$Question 1, shown as an image$

[3]

Answer

Jack is investigating the change in temperature when a piece of magnesium is added to hydrochloric acid.

He uses the equipment in the diagram.

(a)

Jack’s results are in the table.

Repeat	Temperature before adding magnesium (°C)	Temperature after adding magnesium (°C)	Increase in temperature (°C)
1	26	31	5
2	24	30	6
3	24	31	7
4	25	30	5
5	23	27	4

(a)(i)

Give one reason why Jack repeated the experiment.

[1]

Answer

(a)(ii)

Calculate the mean increase in temperature for Jack’s results.

Give your answer as a whole number.

[3]

Answer

(b)(i)

Which word describes the type of reaction Jack has investigated?

Tick (✓) one box.

$Question 2, shown as an image$

[1]

Answer

(b)(ii)

Jack draws the reaction profile for his investigation.

Tick (✓) the correct diagram.

[1]

Answer

(c)

Jack thinks he could improve his method to make the temperature change data more accurate.

(c) Draw one line from an improvement Jack could make to the correct explanation, to make the temperature change data more accurate.

[2]

Answer

Mia is investigating circuits.

She has built the circuit in the diagram.

(a)

Mia wants to increase the potential difference across the bulb. Here are three possible circuits she could make.

All the resistors in each circuit are identical.

Which circuit, A, B or C, will increase the potential difference across the bulb?

Explain why.

Circuit........

Explanation........

[2]

Answer

(b)

Mia builds the circuit in the diagram to investigate current in the circuit.

Mia thinks the reading on ammeter A₁ in the circuit in the diagram will be greater than the reading on A₂ because it is closer to the battery.

Explain why Mia is wrong.

[2]

Answer

(c)(i)

In a circuit, you can measure current, potential difference and resistance.

Draw one line from each circuit measurement to the unit it is measured in.

[2]

Answer

(c)(ii)

Mia’s circuit contains a 3.0 V battery and has a total resistance of 24 maths symbol .

Calculate the current.

Use the equation: current (A) = potential difference (V) ÷ resistance ( maths symbol )

[2]

Answer

This question is about genes and inheritance.

(a)

Draw one line from each genetic term to its correct definition.

Genetic Term
Definition

[3]

Answer

(b)

* Sara breeds rats. Some rats have an inherited genetic condition that means they lack pigment in their skin and hair, so their hair is white. They are called albinos.

Sara breeds a brown female rat and a brown male rat.

Both brown rats have a heterozygous genotype, Bb. B = brown hair b = white hair

Her rats have had several offspring, but none of them has been albino. Sara thinks that her rats could have an albino baby.

Explain why Sara is correct.

Use the Punnet square.

[6]

Answer

(a)

The table gives some information about three sugars that plants make.

Sugar	Formula	Relative Formula Mass (RFM)
Glucose	C₆H₁₂O₆	180
Fructose	C₆H₁₂O₆	180
Sucrose	C₁₂H₂₂O₁₁	342

Glucose and fructose react to make sucrose and water, as shown:

$Question 5, shown as an image$

The relative formula mass of water is 18.

Explain how this reaction demonstrates the conservation of mass.

Use data from the table and the Data Sheet to support your answer.

[3]

Answer

(b)

Plants use glucose in aerobic respiration.

Where does aerobic respiration take place in plant cells?

Tick one (✓) box.

$Question 5, shown as an image$

[1]

Answer

(c)

Respiration produces carbon dioxide. To test for carbon dioxide we use limewater.

The limewater turns cloudy because calcium carbonate forms.

Calculate the percentage by mass of calcium in calcium carbonate, CaCO₃.

Element	Relative Atomic Mass
Carbon (C)	12
Oxygen (O)	16
Calcium (Ca)	40

[4]

Answer

(a)

The graph shows the concentrations of female hormones during one complete menstrual cycle.

(a)(i)

Compare the levels of oestrogen and progesterone in the menstrual cycle up to ovulation.

[3]

Answer

(a)(ii)

On which cycle day does this female ovulate?

[1]

Answer

(a)(iii)

On which cycle day does the progesterone level become higher than the oestrogen level?

[1]

Answer

(b)

Some people are talking about female hormones and the menstrual cycle.

(b)(i)

Which two people are talking about contraception?

[1]

Answer

(b)(ii)

Who might find it hard to predict when they are ovulating?

[1]

Answer

(b)(iii)

Who is preventing ovulation?

[1]

Answer

Eve is investigating transformers.

(a)

The power in the primary coil is equal to the power in the secondary coil.

State in what unit is power measured.

[1]

Answer

(b)

[3]

Answer

(c)

Eve does experiments with five different potential differences in the primary coil and records the potential differences in the secondary coil for each one.

Her results are in the table.

Potential difference in the primary coil (V)	Potential difference in the secondary coil (V)
0.5	1.0
2.0	4.0
6.0	12.5
10.0	20.0
12.0	23.0

(c)(i)

Complete the graph of Eve’s results by plotting the data points and drawing a line of best fit. The first point has been plotted for you.

potential difference in the primary coil (V)

[3]

Answer

(c)(ii)

Describe the relationship shown by the graph.

[2]

Answer

(d)

Transformers are used in the transmission of electrical power. Eve uses her data to explain why transmitting power at higher voltages is a more efficient way to transfer electrical energy.

Complete the sentences.

$Question 7, shown as an image$

As the potential difference across the secondary coil increases, the current in the secondary coil decreases / increases / stays the same. This reduces / stops / increases energy loss in electrical power transmission.

[2]

Answer

Sundip observed her teacher reacting five different metals with water and dilute hydrochloric acid.

(a)

Suggest one safety precaution the teacher should have taken when demonstrating these reactions.

[1]

Answer

(b)

The table shows Sundip’s observations.

Metal Reaction with water	Reaction with dilute hydrochloric acid
A lots of bubbles and fizzing	fizzing and caught fire
B no reaction	no reaction
C no reaction	a few bubbles formed
D caught fire	explosion
E one bubble formed	lots of bubbles formed