P2 Unit 5: Nuclear Fission and Nuclear Fusion

?
  • Created by: nicola
  • Created on: 28-05-15 10:35
What is the structure of a nuclei? 1/2
The number of protons and neutrons can be found from the nuclear sysmbol. E.g C The top number, 14 in this example, tells you the number of protons and neutrons in the nucleus and this is called either the atomic mass number or the nucleon number.
1 of 29
What is the structure of a nuclei? 2/2
The bottom number, 6 in this example, tells you the number of protons in the nucleus and is called either the atomic number or proton number.
2 of 29
How do you calculate the number neutrons?
To calculate the number of neutrons you subtract the protons in the nucleon the number. E.g. 14-6 = 8 nuetrons.
3 of 29
How is the structure of a nuclei lay out?
The Captital letter is the chemiscal symbol are linked. C (carbon) will always have 6 protons / if it has 6 protons its C (carbon).
4 of 29
How can you tell what type of atom it is?
An atom always has the same number of protons and electrons therfore the protons number also tells you the number of electrons in an atom.
5 of 29
What are Ions?
An ion does not have the same number of protons and electrons so it will either have a positive charge if it has lost and electron or a negative charge if it gain an electron.
6 of 29
What is Ionisation?
An atom can be ionised (turn into an ion) by the addition or removal of an electron by ionising radation such as Alpha (rips off electrons by attraction), Beta (knocks off the electrons by repulsion) or Gamma (knocks off electrons by excitation).
7 of 29
What are Alpha, Beta and Gamma formed?
Alpha, Bta and Gamma are all ionising radioations emitted by unstable nucli.
8 of 29
What are Alpha particle? 1/2
An alpha particle is made up of two protons and two neutrons (just like helium neclues). Alpha particles are very ionising as they have a charge of +2 (from the two protons).
9 of 29
What are Alpha particle? 2/2
Due to their large size and ionsing ability they do not penetrate deep into material (stopped by paper, skin or a few cm of air).
10 of 29
What are Beta particles? 1/2
A Beta particle is a fast moving electron (that has been emitted from an unstable nuclei).Beta particles are less strongly ionising than alpha particles aas they only have a charge of -1.
11 of 29
What are Beta particles? 2/2
Due to their small size and smaller ionsing ability they penetrate further into materials (stopped by a few mm of aluminium, few cm of body tissue, a few m of air).
12 of 29
What are Gamma ray? 1/2
A Gamma ray is a type of high energy electromagnetic (EM) wave Gamma rays are only weakly ionising as they have no charge.
13 of 29
What are Gamma ray? 2/2
Due to there low ionising ability and are without mass can penetrste deep into materials. (stooped by thick lead or very thick concrete).
14 of 29
What is nuclear changes? 1/4
A necleus can change by three process which all release energy that can be useful: Neclear Fission, Nuclear Fusion and Radioactive decay.
15 of 29
What is Nuclear Fission? 2/4
Nuclear Fission is when a large nucleaus (such as Uranium) splits into two smaller 'daughter' nuclei and two or three neutrons.
16 of 29
What is Nuclear Fusion? 3/4
Nuclear Fusion is the joining together of two small nuclei (such as Hydrogen).
17 of 29
What is Radioactive Decay? 4/4
Radioactive decay is when a nucleus emits alpha, beta and/or gamma radiation.
18 of 29
What are Chain reactions? 1/2
When uranium fissions it releases two or more neutrons that then go on to cause more uranium nuclei to fission which then release further neutrons etc. this is described as a chained reaction.
19 of 29
What are Chain reactions? 2/2
This reaction is controlled when only one of the neutron released is allowed to go on to fission one more uranium nuclei, so the number of fissions and released of energy per second remains constant.
20 of 29
How do Nuclear Power station work? 1/5
Nuclear power stations use the energy released during fission to heat water into steam that is then used to turn a turbine connected to a generator (magnet inside a coil of wire) that produces electricity.
21 of 29
How are the chain reaction controlled in Nuclear power stations? (1/2) 2/5
The chain reaction is controlled using rods that absorb neutrons and hence stop too many neutrons going on to fussion other uranium nuclei.
22 of 29
How are the chain reaction controlled in Nuclear power stations? (2/2) 3/5
If the chain reaction is going to quickly the control rods are dropped into the reactor if they chain reaction is going too slow they are lifted out.
23 of 29
What are moderator used for in Nuclear power stations? 4/5
A moderator (such as water) is needed between the uranium fuel rod to slow the neutrons so they are travelling at a speed that they can join up with other uranium nuclei and cause them to fission.
24 of 29
What are the daughter nuclei? 5/5
The daughter nuclei produced by nuclear fission are radioactive and therefore dangerous and difficult store.
25 of 29
How does nuclear fusion happen in the sun? 1/2
Stars are powered by nuclear fusion; the joined together of two smaller nuclei.
26 of 29
How does nuclear fusion happen in the sun? 2/2
This requires high temperature and high pressures (found in stars) to force the two positively charged nuclei (because of the protons) to get close enough to fuse as they would naturally repel (as like charges repel).
27 of 29
What are fusion power stations? How do fusion power station work? 1/2
The high pressure and temperature needed for fusion are difficult to produce and therefore a commercial fusion power station are not yet in operation.
28 of 29
What are fusion power stations? How do fusion power station work? 2/2
A fusion would be better than fission power stations as the 'fuel' required is more easily acquired and the waste products are not radioactive or dangerous.
29 of 29

Other cards in this set

Card 2

Front

What is the structure of a nuclei? 2/2

Back

The bottom number, 6 in this example, tells you the number of protons in the nucleus and is called either the atomic number or proton number.

Card 3

Front

How do you calculate the number neutrons?

Back

Preview of the front of card 3

Card 4

Front

How is the structure of a nuclei lay out?

Back

Preview of the front of card 4

Card 5

Front

How can you tell what type of atom it is?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Physics resources:

See all Physics resources »See all Nuclear Fission and Nuclear fuision resources »