Science (Double Award) — Physics

Properties of Radiation (Edexcel IGCSE Science): Exam Questions

Exam code:4SD0

27 questions · 93 marks · ≈ 2 hours

Guided practice

11 markeasy

(a)

Carbon-14 is a radioactive isotope of carbon.

It has the symbol

7-1-mcq-q6-question

The number of nucleons in a carbon-14 nucleus is

Choose your answer

21 markeasy

(b)

When carbon-14 decays it emits a beta particle.

What is a beta particle?

Choose your answer

An electron

A neutron

A nucleus

A proton

31 markeasy

(b)

Which of these is the same as an electron?

Choose your answer

Alpha particle

Beta particle

Gamma ray

X-ray

46 markseasy

2 marks

(a)

Sodium-24 is a radioactive isotope.

What are isotopes?

Your answer

4 marks

(b)

Sodium-24 decays by emitting beta particles.

(i) Describe the nature of a beta particle.

(1 mark)

(ii) Name a piece of equipment that can be used to detect beta particles.

(1 mark)

(iii) Describe how a detector can be used with sheets of lead, aluminium and paper to show that a sample of sodium-24 emits beta particles.

(2 marks)

Your answer

How did you do?/ 6

54 markseasy

3 marks

(a)

Scientists use the term radiation in different ways.

Sometimes radiation means streams of particles and sometimes radiation means high frequency waves.

Draw a straight line from each description to the type of radiation it describes.

7-1-sqs-q6new-question

Your answer

1 mark

(d)

People who work with ionising radiation need to measure the amount of radiation they are exposed to. For many years, a film badge was used to detect the radiation.

State the name of another device that can be used to detect alpha radiation.

Your answer

How did you do?/ 4

62 markseasy

(b)

The radioactive nuclei in a source emit beta radiation.

What effect does the emission of a beta particle have on a nucleus?

Your answer

How did you do?/ 2

73 markseasy

2 marks

(a)

There are different types of ionising radiation.

Type of ionising radiation	Charge	Emitted by
alpha particle		unstable nuclei
beta particle	-	unstable nuclei
gamma ray	0

Complete the table to show the properties of each type.

Your answer

1 mark

(c)

A radioactive source contains strontium-90.

A strontium-90 nucleus emits a beta particle.

1-7-1-13

Complete the equation to show how strontium-90 decays.

Your answer

How did you do?/ 3

83 marksmedium

(a)

Radon is a gas produced by some types of rocks.

Radon is a natural source of radioactivity.

What is the name for this radioactivity?

Choose your answer

Chain reaction

Background radiation

Radioactive dating

Radiotherapy

(c)

Radon-222 and radon-220 are both isotopes of radon. A nucleus of radon-222 has 86 protons.

How many protons are there in a nucleus of radon-220?

Choose your answer

less than 86

more than 86

none

(c)

Radon-222 and radon-220 are both isotopes of radon. A nucleus of radon-222 has 136 neutrons.

How many neutrons are there in a nucleus of radon-220?

Choose your answer

134

136

220

91 markmedium

(a)

Vanadium-50 is an isotope of vanadium.

It has the symbol $V_{23}^{50}$

The number of neutrons in a vanadium-50 nucleus is

Choose your answer

104 marksmedium

(a)

Which of these particles has the largest mass?

Choose your answer

Alpha particle

Beta particle

Neutron

Proton

(a)

Which of these particles has the largest charge?

Choose your answer

Alpha particle

Beta particle

Neutron

Proton

(c)

The maximum range of a beta particle in air is about

Choose your answer

50 mm

50 cm

50 m

50 km

(d)

When a nucleus emits a beta particle

Choose your answer

The nucleon number decreases by 1

The nucleon number increases by 1

The proton number decreases by 1

The proton number increases by 1

111 markmedium

(a)

When an unstable nucleus emits an alpha particle, its atomic (proton) number

Choose your answer

Increases by 1

Stays the same

Decreases by 2

Decreases by 4

121 markmedium

(b)

Which of these has a mass (nucleon) number of 4?

Choose your answer

Alpha particle

Beta particle

Gamma ray

X-ray

131 markmedium

(b)

Which of these is the most ionising?

Choose your answer

Alpha particle

Beta particle

Gamma ray

X-ray

141 markmedium

(a)

When an unstable nucleus emits an alpha particle, its mass (nucleon) number

Choose your answer

Increases by 1

Stays the same

Decreases by 2

Decreases by 4

152 marksmedium

(a)

The atomic (proton) number for iodine-131 is

Choose your answer

131

(a)

lodine-131 is a radioactive isotope that emits beta particles.

The equation for this decay is

mcq-7-1-20

The mass (nucleon) number for Xe is

Choose your answer

−1

131

161 markmedium

(b)

Which of these describes what happens to the strontium-90 nucleus when it emits a beta particle?

Choose your answer

The number of protons stays the same

The number of protons increases

The number of neutrons stays the same

The number of neutrons increases

178 marksmedium

6 marks

(a)

Tritium is an isotope of hydrogen that decays by emitting beta particles. It is used in some luminous signs.

The symbol for tritium is ${}_{1}^{3}H$ .

(i) Determine the number of protons and the number of neutrons in a single atom of tritium.

(2 marks)

(ii) Describe three differences between an alpha particle and a beta particle.

(3 marks)

(iii) Suggest why tritium cannot emit alpha particles.

(1 mark)

Your answer

2 marks

(b)

Tritium is used in this luminous sign.

7-1-sqs-q1b-question

In this sign

The letters are made up of glass tubes containing tritium gas
The inside of each tube is coated with a phosphor
The phosphor emits light when beta particles hit it

Suggest why this sign is safe to use even though beta particles are ionising and can be dangerous.

Your answer

How did you do?/ 8

1811 marksmedium

2 marks

(a)

A teacher uses this apparatus to demonstrate radioactivity to his students.

7-1-sqs-q2a-question

The teacher needs to take some safety precautions.

Put one tick (✓) on each row to show whether the safety precaution is needed or not. Two have been done for you.

safety precaution	needed	not needed
not touch the source with bare hands	✓
use tongs
wear gloves		✓
wear googles
students sit at least two metres away
wear a lead apron
store source in a lead box

Your answer

3 marks

(b)

The teacher uses this method to investigate radioactivity.

Place the detector 10 cm from the radioactive source
Record the count with different absorbent materials between the source and the detector
Repeat the investigation using a different radioactive source
Also repeat the investigation without a source

The table shows his results.

Source used	Counts in 30 s for each material
	5 mm of aluminium	5 mm of lead	0.2 mm of paper	5 mm of plastic	5 mm of stone	5 mm of wood
barium-133	3 843	1 989	not taken	4 551	10 408	4 557
strontium-90	14	15	42 770	182	13	331
none	15	15	14	15	14	15

(i) State why the teacher keeps the distance constant between the source and the detector.

(1 mark)

(ii) Explain why there is a reading when no source is used.

(2 marks)

Your answer

6 marks

(b)

(i) Explain which of the materials the teacher used is the best absorber of radiation.

(3 marks)

(ii) A student makes this conclusion.

'Stone is the worst absorber of radiation.'

Evaluate this conclusion

(3 marks)

Your answer

How did you do?/ 11

1914 marksmedium

3 marks

(b)

The table describes the nuclei of four atoms.

uranium-234	uranium-235	plutonium-238	americium-238
${}_{92}^{234}U$	${}_{92}^{235}U$	${}_{94}^{238}{Pu}$	${}_{95}^{238}{Am}$

(i) Which two nuclei have the same number of protons?

(1 mark)

(ii) Which two nuclei have the same number of nucleons?

(1 mark)

(iii) Which two nuclei have the same number of neutrons?

(1 mark)

Your answer

3 marks

(c)

All of the nuclei are unstable and have a different half-life.

(i) Explain what is meant by the term unstable.

(1 mark)

(ii) Explain what is meant by the term half-life

(2 marks)

Your answer

5 marks

(d)

When plutonium decays, it emits an alpha particle and a gamma ray.

(i) Complete the decay equation for plutonium-238.

$Pu_{94}^{238} \rightarrow \ \\alpha_{\text{square}}^{4} + \mathrm{X}_{\text{square}}^{\text{square}} + \ \\gamma_{0}^{\text{square}}$

(4 marks)

(ii) Use information from the table in part (a) to identify element X.

(1 mark)

Your answer

3 marks

(e)

The nucleus of americium-238 can absorb an electron. When this happens, one of the protons in the nucleus becomes a neutron.

This equation describes the process.

p _ 1 ^ 1 + e _ - 1 ^ 0 -> n _ 0 ^ 1

(i) Describe how this process affects the proton number and the nucleon number of the nucleus that absorbs the electron.

(2 marks)

(ii) Identify the new nucleus formed by this process.

(1 mark)

Your answer

How did you do?/ 14

205 marksmedium

The table shows the nature of alpha and beta particles.

p_bgScbW_7-1-q10-

Explain why alpha particles and beta particles have different penetrating powers.

Your answer

How did you do?/ 5

211 markhard

(a)

A doctor uses gamma radiation to produce an image of a person's brain.

A radioactive isotope called technetium-99m is used in this process.

Technetium-99m emits gamma rays and has a short half-life.

7-1-mcqs-q1-question

Gamma radiation consists of

Choose your answer

Electromagnetic waves

Negatively charged particles

Positively charged particles

Unstable atoms

221 markhard

(a)

The table describes the nuclei of four atoms.

7-1-mcqs-q2-question

Atoms contain electrons.

Which nucleus needs the largest number of electrons to form a neutral atom?

Choose your answer

Uranium-234

Uranium-235

Plutonium-238

Americium-238

231 markhard

(a)

Tellurium-120 is an isotope of tellurium.

It has the symbol ${}_{52}^{120}{Te}$

The number of protons, neutrons and electrons in a neutral tellurium-120 atom is

Choose your answer

p = 120n = 52e = 120

p = 120n = 68e = 68

p = 52n = 120e = 120

p = 52n = 68e = 52

241 markhard

(b)

Compared to a beta particle, an alpha particle

Choose your answer

Causes less ionisation

Has less charge

Has less mass

Has less penetrating power

259 markshard

3 marks

(a)

The grid shows the number of neutrons and the number of protons in some isotopes formed during successive radioactive decays.

7-1-sqs-q7a-question

(i) What are isotopes?

(2 marks)

ii) Why are some isotopes described as stable?

(1 mark)

Your answer

4 marks

(b)

(i) Use the grid in part (a) to calculate the number of neutrons in a $\text{Po}_{}^{210}$ nucleus.

(1 mark)

(ii) Describe what happens to the number of protons and the number of neutrons when a nucleus of $\text{Pb}_{}^{210}$ decays to form $\text{Bi}_{}^{210}$ .

(2 marks)

(iii) State the type of decay that occurs when $\text{Pb}_{}^{210}$ decays to form $\text{Bi}_{}^{210}$ .

(1 mark)

Your answer

2 marks

(c)

Explain why the mass (nucleon) number and the atomic (proton) number do not change when a gamma ray is emitted from a nucleus.

Your answer

How did you do?/ 9

265 markshard

2 marks

(a)

Alpha particles, beta particles and gamma rays have different properties.

Complete the table by ticking the correct type of radiation for each property. The first one has been done for you.

Property	Type of radiation
	alpha particles	beta particles	gamma rays
most ionising	✓
largest mass
most penetrating
highest speed
negatively charged

Your answer

3 marks

(b)

The symbol for the structure of an alpha particle is

$\ \\alpha_{2}^{4}$

(i) State the number of neutrons and the number of protons in an alpha particle.

(2 marks)

(ii) Suggest why alpha radiation is more ionising than beta or gamma radiation.

(1 mark)

Your answer

How did you do?/ 5

274 markshard

(a)

Scientists use deflection in an electric field to help distinguish between different types of radiation.

The diagram shows a beam containing several types of radiation. This beam travels in a vacuum between two charged plates.

Some of the radiation is deflected upwards, some is deflected downwards, and some are not deflected at all.

7-1-sqs-q9-new-question

Put one tick in each row to show the correct deflection for each type of radiation.

One has been done for you.

Type of radiation	Deflected upwards	Deflected downwards	Not deflected
alpha	✓
beta
gamma
neutrons
protons

Your answer

How did you do?/ 4

Type of ionising radiation

Charge

Emitted by

alpha particle

unstable nuclei

beta particle

unstable nuclei

gamma ray

safety precaution

needed

not needed

not touch the source with bare hands

✓

use tongs

wear gloves

✓

wear googles

students sit at least two metres away

wear a lead apron

store source in a lead box

Source used

Counts in 30 s for each material

5 mm of aluminium

5 mm of lead

0.2 mm of paper

5 mm of plastic

5 mm of stone

5 mm of wood

barium-133

3 843

1 989

not taken

4 551

10 408

4 557

strontium-90

42 770

182

331

none

uranium-234

uranium-235

plutonium-238

americium-238

{}_{92}^{234}U

{}_{92}^{235}U

{}_{94}^{238}{Pu}

{}_{95}^{238}{Am}

Property

Type of radiation

alpha particles

beta particles

gamma rays

most ionising

✓

largest mass

most penetrating

highest speed

negatively charged

Type of radiation

Deflected upwards

Deflected downwards

Not deflected

alpha

✓

beta

gamma

neutrons

protons