nuclear nat 5
DESCRIPTION
Nuclear Nat 5. 5. 1. 2. 3. 4. 6. 7. 8. 9. 10. 12. 11. Why is radiation emitted from atoms?. Because there nucleus is unstable. Due to the proton to neutron ratio. A alpha particle consists of…. - PowerPoint PPT PresentationTRANSCRIPT
Nuclear Nat 5
1 2 3 4 5
6 7 8 9 10
12 11
Why is radiation emitted from atoms?
Because there nucleus is unstable. Due to the proton to neutron ratio.
A alpha particle consists of…
2 protons and 2 neutrons: it is a a helium atom.
Beta radiation is described as …
A high speed electron
Gamma radiation is described as …
A wave
Alpha is stopped by…Thin paper and a few cm of air.
Beta is stopped by…Thick lead, concrete and Aluminium.
Gamma is stopped by…Concrete or lead.
6g of a radioactive isotope of 60Co has a half-life of 5 yrs. how much of this isotope would be left after 20 yrs?
The half life of a radio active isotope is a measure of the time is takes for activity to be reduced by half. Over a period of 20 years, 4 half-lives would be needed .
60Co 60Co 60Co 60Co 60Co
6g 3g 1.5g 0.75g 0.375g
What is the result of an atom losing an alpha
particle?
An alpha particle is a helium nucleus. So is made up from 2 protons and 2 neutrons. It has a atomic number of 2 and a mass number of 4. So the atomic number decreases by 2 and the mass number decreases by 4.
What type of reaction is occurring in the process below?
Nuclear fission this involves the splitting of a nucleus into two nucleui.
3
920
1U
236+
56
Ba 142
36
Kr 91
+
What is produced (X) when 238U
is combined with a neutron.
Adding a neutron means the mass number willincrease by 1, but the atomic number will not change.
n 01
U 238+
e -1
0+X
X =93
Pu 239
131I can be used to study diseased thyroid glands. Its half-life is 8 days. A patient was given 0.0053 mol of this isotope. How many grams would be left after 16 days?
The mass of 131I in 0.0053g = n (number moles) = mass/gfmSo mass = n x gfm = 0.0053x131 =0.694g
131I 131I 131I
0.694g 0.347g 0.174g
8 16