sp6 end of unit test

SP6

1

End of Unit Test Higher

© Pearson Education Ltd 2019. Copying permitted for purchasing institution only. This material is not copyright free.

Name Class Date

1 Atoms are very small.

a What is the approximate value for the diameter of an atom?

Tick one box.

A 6 × 10–16 m (0.000 000 000 000 000 6 m)

B 6 × 10–11 m (0.000 000 000 06 m)

C 6 × 10–6 m (0.000 006 m)

D 0.6 mm (0.000 6 m)

(1)

b A helium atom has two protons, two neutrons and two electrons. Draw a diagram of a helium atom.

(2)

c Describe how electromagnetic radiation can ionise an atom.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

(2)

(Total for Question 1 = 5 marks)

SP6

2



2 A student investigates the absorption of beta (β) particles by playing cards.

Figure 1 shows the apparatus the student uses.

Figure 1

The student changes the number of playing cards between the source and the detector.

The student records the number of counts in each minute in Figure 2.

a i Complete Figure 2 below for 39 cards.

(1)

ii Complete Figure 2 below for 52 cards.

(1)

Number of cards used

Counts on meter in each minute

Corrected count rate (count rate – background count)

Change in count rate from previous

0 1278 1158 N/A

13 995 875 283

26 843 723 152

39 680

52 576

Figure 2

b Explain what is meant by the term ‘background count’.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

(2)

SP6

3



c Describe the trend shown in the ‘change in count rate from previous’ column.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

(2)

d State two ways in which you could improve the experiment.

1 _________________________________________________________________________________

_________________________________________________________________________________

2 _________________________________________________________________________________

_________________________________________________________________________________

(2)

e The student thought that the source might be emitting some alpha (α) particles as well as the beta (β) particles.

Explain how the student could test whether alpha particles were emitted from the source.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

(2)


3 a State one advantage and one disadvantage of producing electricity using nuclear fuel instead of coal.

Advantage:

__________________________________________________________________________________

__________________________________________________________________________________

Disadvantage:

__________________________________________________________________________________

__________________________________________________________________________________

(2)

SP6

4



b Explain the role of a moderator in a nuclear reactor.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

(2)

c i Explain how gamma rays are produced in a PET scanner.

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

(2)

ii State why the source of positrons has to be nearby.

_______________________________________________________________________________

_______________________________________________________________________________

(1)

d Complete the equation which shows the fission of a uranium nucleus

235 1 144 90 92 0 56 36U + n Ba + Kr +

(2)


4 a A scientist started with a mass of 0.05 g of a radioactive isotope.

After 12 hours the mass of that isotope was 0.0125 g.

Calculate the half-life of the sample. State its unit.

half-life of sample = _________ unit _________

(3)

SP6

5



b The fraction of mass left from a radioactive sample is related to the half-life of the sample by the

equation:

fraction left = 0.5n1, where n is the number of half-lives.

Calculate the fraction left when n = 4

fraction left = _________

(2)


5 The chart in Figure 3 shows how the number of protons and neutrons varies for some atoms, P to W.

Figure 3

a Which of these is an isotope of atom Q?

Tick one box.

A R

B S

C T

D U

(1)

SP6

6



b Which atom has a mass number of 2 lower than atom T?

Tick one box.

A S

B U

C V

D W

(1)

c Atom Q emits an alpha particle.

State the letter of the atom produced. _________

(1)

d The nucleus of atom Q decays to form the nucleus of atom U.

Explain what has happened.

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

__________________________________________________________________________________

(2)


SP6

7



6 Ionising radiation, such as alpha particles and gamma rays, can be dangerous.

Users need to take safety precautions to reduce the effects of ionising radiation.

Describe the dangers of alpha radiation and gamma radiation.

Explain how safety precautions can reduce the effects of these dangers.

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

_____________________________________________________________________________________

(6)


TOTAL FOR PAPER = 40 MARKS

sp6 end of unit test

Documents