Brainscape's Knowledge GenomeTM

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


See full index

physics > atomic structure > Flashcards

atomic structure Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

what is the atomic theory and who proposed it

A

the theory that everything is made up of tiny particles which cannot be broken down any further and are separated by empty space, proposed by democritus around 500 BC

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

what was john daltons theory on atomic structure

A

atoms are solid spheres and different types of spheres might make up the different elements

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

who came up with the plum pudding model

A

jj thomson

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

what was ernest rutherford’s experiment

A

directing alpha particles into a thin sheet of gold

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

what is the nuclear model

A

atoms are made up of a compact nucleus and are surrounded by a cloud of negative charge

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

what was the flaw in rutherford’s nuclear model

A

there was nothing stopping the cloud of negative charge from rushing into the nucleus meaning that the atom should just automatically collapse

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

how did niels bohr improve on the nuclear model

A

he said that there were electrons orbiting the nucleus which prevents the atom from collapsing

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

which two science discovered protons and neutrons

A

protons - rutherford

neutrons - chadwick

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

when can an electron jump into another shell

A

only when it has gained enough energy

- we say that the electron is ‘excited’

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

where does the energy required for an electrons to jump into a higher energy level come from

A

from electromagnetic radiation

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

what happens when an electron returns to its original, lower energy level

A

energy is released as electromagnetic radiation

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

what is ionisation

A

when one of the outermost electrons gains so much energy that it is able to completely leave the atom
- this leaves the atom with a positive charge

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

what is radioactive decay

A

when isotopes emit something so that they can become more stable

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

what are alpha particles made up of

A

2 protons and 2 neutrons

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

what are alpha particles made up of

A

2 protons and 2 neutrons

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

how penetrative are alpha particles

A

alpha particles are not very penetrative

  • stopped in a few cm of air
  • absorbed by a single sheet of paper
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how penetrative are alpha particles

A

alpha particles are not very penetrative

  • stopped in a few cm of air
  • absorbed by a single sheet of paper
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how ionising are alpha particles

A

they are very strong ionising due to their large size and strong charge

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

what are beta particles

A

just an electron

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

where to beta particles come from

A
  • one of the atom’s neutrons decays into a proton and electron
  • the proton stays in the nucleus while the electron is emitted out at high speed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how ionising are beta particles

A

moderately ionising due to their small size

21
Q

how penetrative are beta particles

A
  • stopped by several metres of air

- stopped by 5mm of aluminium

22
Q

how penetrative are beta particles

A
  • stopped by several metres of air

- stopped by 5mm of aluminium

23
Q

what are gamma rays

A

waves of electromagnetic radiation

24
Q

how ionising are gamma rays

A

they are weakly ionising as they pass through material easily

25
Q

how penetrative are gamma rays

A

very penetrative

  • can travel long distances in air
  • stopped by thick sheets of lead
  • stopped by multiple metres of concrete
26
Q

what happens to the mass and atomic number when an alpha particle is emitted

A

mass number - 4

atomic number - 2

27
Q

what happens to the mass and atomic number when beta radiation is emitted

A

mass number stays the same

atomic number + 1 (because it gains a neutron)

28
Q

what is meant by the activity of the sample and what is it measured in

A

the overall rate of decay

- measure in becquerels (Bq)

29
Q

what is meant by half-life

A

the time taken for the number of decays to halve

the time taken for the number of radioactive nuclei in a sample to halve

30
Q

what device is used to find the activity of a radioactive material

A

geiger-muller tube and counter

31
Q

what is irradiation

A

the process by which objects are exposed to radiation

32
Q

what is contamination

A

when radioactive particles get onto other objects

33
Q

what determines how harmful radiation is

A
  • type of radiation
  • where you’re exposed to it
  • the amount of radiation you receive
34
Q

why are ionising radiations dangerous

A

they can enter living cells and interact with the molecules inside
- ionises our DNA which can cause mutations (like cancer)

35
Q

what is the most harmful type of radiation

A

alpha radiation as it is very ionising

36
Q

what is the least harmful radiation

A

radio waves

37
Q

what type of radiation is dangerous if it is coming from an external source

A

beta and gamma

38
Q

how can we protect ourselves from irradiation and contamination

A
  • wearing gloves and overalls
  • using tongs to pick of radioactive material
  • keeping the item in a lead lined box
39
Q

how can radiation be used to help treat cancer

A

the radiation can help kill cancer cells however this will make the patient experience many side effects like hair loss and vomiting
- we call this radiotherapy

40
Q

what are medical tracers

A

injecting a patient with radioactive material to track the movement of isotopes around the body by tracking the radiation they emit

41
Q

what is nuclear fission

A

the splitting up of a large and unstable nuclei into smaller nuclei while also releasing large amounts of energy

42
Q

what are the two ways nuclear fission can happen by

A
  • spontaneously

- absorbing a neutron

43
Q

what are the steps of nuclear fission

A
  1. fire a neutron into the nuclei
  2. this causes it to become unstable and then split into two daughter nuclei and a few neutrons ( + loads of energy)
  3. the daughter nuclei then repeat the process
44
Q

what is the purpose of control rods

A

to be lowered into the nuclear reaction to absorb neutrons as this helps control the rate of nuclear fission

45
Q

how is the energy from nuclear reactors used

A

the energy is used to heat up water to create steam, the steam then drives the turbines which are connected to a electricity generator

46
Q

what are the pros of nuclear energy

A
  • uranium and plutonium fuel is relatively cheap
  • large and steady amount of energy
  • doesn’t produce greenhouse gases
47
Q

what are the pros of nuclear energy

A
  • uranium and plutonium fuel is relatively cheap
  • large and steady amount of energy
  • doesn’t produce greenhouse gases
48
Q

what are the cons of nuclear energy

A
  • nuclear power plants are very expensive to build
  • nuclear waste is expensive to get rid of
  • risk of major disaster
49
Q

what is nuclear fusion

A

when two lighter nuclei fuse to form a larger nuclei

50
Q

what did nuclear fusion make/fuel

A

nuclear fusion is how all elements heavier than hydrogen were made and it is what fuels stars

physics (5 decks)

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