General Knowledge - Chemistry - Discussion
Discussion Forum : Chemistry - Section 1 (Q.No. 67)
67.
The half life period of an isotope is 2 hours. After 6 hours what fraction of the initial quantity of the isotope will be left behind?
Discussion:
6 comments Page 1 of 1.
Vikie said:
4 years ago
Yes, It's 1/8.
Tahira said:
8 years ago
At 2hours its amount is 1/2.
At 4hours its amount is 1/2*1/2.
At 4hours its amount is 1/2*1/2*1/2=1/8.
At 4hours its amount is 1/2*1/2.
At 4hours its amount is 1/2*1/2*1/2=1/8.
(5)
Bikash Ranjan Parhi said:
1 decade ago
Now the half life of the isotope is given 2 hours. After 6 hours the no of half lives will be 3.
So the The amount of radioactive isotope remaining can be calculated as:
Nt = No x 1/2^n where, Nt is the amount of radio isotope remaining. No is the original amount of radio isotope.
N is the no of half lives.
Now let the original amount of isotope is one, then by using the formula we can calculate the remaining of isotope as:
Nt = 1x1/2^3
= 1x1/8
= 1/8
So the The amount of radioactive isotope remaining can be calculated as:
Nt = No x 1/2^n where, Nt is the amount of radio isotope remaining. No is the original amount of radio isotope.
N is the no of half lives.
Now let the original amount of isotope is one, then by using the formula we can calculate the remaining of isotope as:
Nt = 1x1/2^3
= 1x1/8
= 1/8
(2)
Soumyojit said:
1 decade ago
1.........(1-1/2)=1/2......(1/2-1/4)=1/4........(1/4-1/8)=1/8
t=0 t=2 hrs. t=(2+2)=4 hrs. t=(2+2+2)=6 hrs.
The answer should be 1/8.
t=0 t=2 hrs. t=(2+2)=4 hrs. t=(2+2+2)=6 hrs.
The answer should be 1/8.
Sumedh said:
1 decade ago
The answer should be 1/8.
ULAB said:
1 decade ago
1----------- 1/2------------1/4-----------1/8
1 2 3
1*2 2*2 3*2
2Hrs 4Hrs 6Hrs
1 2 3
1*2 2*2 3*2
2Hrs 4Hrs 6Hrs
(1)
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