Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GCSE PHYSICS > Atomic structure > Flashcards

Atomic structure Flashcards

1
Q

What is the plum pudding model?

A

What atoms were considered to be before Rutherford’s experiment. Electrons were negative ‘plums’ embedded in a ball of positive ‘pudding’.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the mass of a proton?

A

1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the mass of a neutron?

A

1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the mass of an electron?

A

0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the charge of a proton?

A

+1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the charge of a neutron?

A

0

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the charge of an electron?

A

-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the outcomes of Rutherford’s experiment?

A

Most of the fast, highly charged particles went whizzing through undeflected.
Some of the alpha particles were reflected back through at large angles.
A small number of the alpha particles (1/8000) were deflected back.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What were the conclusions of Rutherford’s experiment?

A

1) Most of the atom is empty space.
2) There is a positive charge somewhere in the atom.
3) the nucleus carries most of the atom’s mass, also the concentrated mass is tiny.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are isotopes?

A

Isotopes are atoms with the same number of protons but a different number of neutrons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the atomic number?

A

Number of protons or electrons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the mass number?

A

Number of protons plus number of neutrons. (Mass number is the bigger number)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are non stable isotopes?

A

They tend to be radioactive, which means they decay into other elements and give out radiation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do unstable isotopes become stable?

A

By releasing different types of particles, this is radioactive decay.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are elements that undergo radioactive decay?

A

Radioisotopes/ radionuclides.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do radioactive substances do?

A

Give out radiation from the nuclei of their atoms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What sort of process is radioactivity?

A

Random.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the three types of radiation?

A

Alpha, Beta and Gamma

There is a 4th type of decay that can emit a neutron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe alpha.

A

Has a helium nucleus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe Beta.

A

A high speed electron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe Gamma.

A

A wave of electromagnetic radiation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the electric charge of alpha?

A

+2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the electric charge of Beta?

A

-1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the electric charge of Gamma?

A

0

25
Q

What is the relative atom mass of alpha?

A

4

26
Q

What is the relative atomic mass of Beta?

A

1/2000

27
Q

What is the relative atomic mass of Gamma?

A

0

28
Q

What is the penetration power of alpha?

A

The least

Cannot pass through skin.

29
Q

What is the penetration power of Beta?

A

Medium

Cannot pass through aluminium.

30
Q

What is the penetration power of Gamma?

A

The most

Can pass through lead.

31
Q

What ionising effect does alpha have?

A

The most.

32
Q

What ionising effect does Beta have?

A

Medium

33
Q

What ionising effect does Gamma have?

A

The least.

34
Q

What does the effects of a magnetic/ electric field on Alpha?

A

It’s deflected a little.

35
Q

What does the effects of a magnetic/ electric field on Beta?

A

It’s deflected a lot.

36
Q

What does the effects of a magnetic/ electric field on Gamma?

A

Nothing.

37
Q

What is the general formulae of alpha?

A

Reduces atomic number by 2 and mass number by 4.

38
Q

What is the general formulae for Beta?

A

Increases atomic number by 1.

39
Q

What is the general formulae for Gamma?

A

There is no change.

40
Q

What is alpha used for?

A

Smoke alarms.

Alpha ionises the air and causes charged particles to flow, if smoke is present this stops and the alarm goes off.

41
Q

What is Beta used for?

A

Thickness control

E.g if aluminium foil is too thick less Beta gets through but if it’s too thin more Beta gets through.

42
Q

What is Gamma used for?

A

Radiotherapy
Gamma rays are aimed at a tumour, a high dose kills cancer cells.
Sterilisation of food and surgical equipment.
Will kill all microbes on food. Does not use high temperature, so things like fruit and plastic can be sterilised without being damaged. Does not leave food radioactive.

43
Q

What is half life?

A

Time for half the unstable nuclei to decay.

44
Q

What is a short half life?

A

When the activity falls quickly because lots of the nuclei decay quickly.

45
Q

What is a long half life?

A

He activity falls more slowly because most of the nuclei don’t decay for a long time.

46
Q

How is cancer caused by radiation?

A

Alpha, beta and Gamma can enter cells which collide with molecules. These collisions cause ionisation, which damages or destroys the molecules. Small doses can lead to mutant cells which divide uncontrollably.

47
Q

What safety precautions should you take when handling radioactive substances?

A

Never allow skin contact with a source, always use tongs.
Hold the source am arms length away from you so that the amount of radiation that hits you decreases.
Always store the sample in a lead box- lead absorbs radiation.

48
Q

What is radiation?

A

Energy transferred by particles or waves emitted from the nucleus.

49
Q

What is a nucleon?

A

Collective names for protons and neutrons.

50
Q

What is irradiation?

A

Exposure to radiation.

51
Q

What is a bequerel (Bq)?

A

The unit of activity.

52
Q

What is activity?

A

Number of decay per second.

53
Q

What is nuclear fission?

A

When a heavy nucleus splits in two smaller nuclei which releases energy. The isotopes most used in nuclear reactors are uranium (235) and plutonium (239).

54
Q

What 3 things are produced in a single fission reaction?

A
  • Energy in the form of heat
  • Two or three smaller nuclei
  • 3/a few moving single neutrons
55
Q

How does a chain reaction work?

A

A neutron hits a nucleus.
The nucleus splits into smaller nuclei and some more neutrons.
These hit more nuclei.

56
Q

What is nuclear fusion?

A

When two smaller atoms join together to form a bigger one.

57
Q

What does nuclear fusion generate?

A

Heat energy

58
Q

How does nuclear fusion work with a gas?

A

If you super heat a gas, the atom has so much energy that its electrons become excited and shed off.
This ionises the particle allowing them to conduct electricity.
As the electrons return to their low energy state, the give off EM radiation.

59
Q

How do you start a fusion reaction?

A

The fuel must be heated at a temperature of about 15 million degrees. This makes plasma, a gas which the electrons have been stripped from the nuclei.

GCSE PHYSICS (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions