some elements have atoms which are unstable. these atoms spontaneously transmutate from one element...
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Some elements have atoms which are unstable.These atoms spontaneously transmutate from one element to another.These types of transmutations include beta decay, electron capture and alpha decay.Alpha decay involves the emission of a helium nucleus.
92
235U 2
4He +
90
231Th
Different radioactive isotopes decay at different rates.If 100 g of a radioactive material decays for 10 years and 50 g remains this substance is said to have a half life of 10 years.
5 y 5 y
After 10 y only 50 g remain
If 200 g of a radioactive material with a half-life of 5 years, is left to decay for 10 years how much of the original material is left?
200 g -------> 100 g -------> 50 g
If 200 g of a radioactive material with a half-life of 5 years, is left to decay for 10 years how much of the original material is left?
200 g ------->
200 g
If 200 g of a radioactive material with a half-life of 5 years, is left to decay for 10 years how much of the original material is left?
200 g -------> 100 g
100 g left after 5 years
If 200 g of a radioactive material with a half-life of 5 years, is left to decay for 10 years how much of the original material is left?
200 g -------> 100 g -------> 50 g
50 g left after 10 years
If 200 g of a radioactive material with a half-life of 5 years, is left to decay for 10 years how much of the original material is left?
200 g -------> 100 g -------> 50 g ----> 25g
25 g left after 15 years
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
512 g
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
256 g
512 g ---> 256 g25 da
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
128 g
512 g ---> 256 g ---> 128 g25 da 25 da
Total - 50 da
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
64 g
512 g ---> 256 g ---> 128 g ---> 64 g25 da 25 da 25 da
Total - 75 da
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
32 g
512 g ---> 256 g ---> 128 g ---> 64 g ---> 32 g25 da 25 da 25 da 25 da
Total - 100 da
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
16 g
512 g ---> 256 g ---> 128 g ---> 64 g ---> 32 g25 da 25 da 25 da 25 da
Total - 125 da 16 g25 da
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
512 g ---> 256 g ---> 128 g ---> 64 g ---> 32 g25 da 25 da 25 da 25 da
Total - 150 da 16 g25 da
8 g
8 g
25 da
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
512 g ---> 256 g ---> 128 g ---> 64 g ---> 32 g25 da 25 da 25 da 25 da
Total - 175 da 16 g25 da
4 g
8 g
25 da
4 g
25 da
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
512 g ---> 256 g ---> 128 g ---> 64 g ---> 32 g25 da 25 da 25 da 25 da
Total - 200 da 16 g25 da
2 g
8 g
25 da
4 g
25 da
2 g25 da
Show the decay sequence for 512 g of a substance with a half-life of 25 da.
512 g ---> 256 g ---> 128 g ---> 64 g ---> 32 g25 da 25 da 25 da 25 da
Total - 225 da 16 g25 da
1 g
8 g
25 da
4 g
25 da
2 g25 da
1 g25 da
If U-235 has a half-life of 7.1 x 108 y. How many years would it take 32 g to decay to 2 g?32 g --> 16 g --> 8 g --> 4 g --> 2 g4 half lifes2.84 x 109 y.
Cs-136 has a half-life of 13 da. If 1024 g was left to decay for 65 da how much of the original material would be left?65/13 = 5 hl1024 g -> 512 g -> 256 g -> 128 g -> 64 g -> 32 g
or 1024 g x (1/2)5 = 32 g
To find the quantity of material remaining use this formula
Massremaining =
OriginalMass
x 12
# of Half-lives
Pb-212 has a half-life of 10.6 h. If 12.5 g of Pb-212 is left for 84.8 h how much of the original material is left?
Massremaining =
OriginalMass
x 12
# of Half-lives
12.5 g x (0.5)84.8/10.6
= 0.0488 g