39Approximate them to 3? :D
40 atoms of radioactive element x( t→1/2=10 hours) r present.how many r likely to remain after 40 hours....
a. 1
b. 2.5
c. 5
d. 3
since radioactivity follows 1st order kinetics so t half should remain constant and by doing dat d ans. which u will get is 2.5........but atoms can't be in fraction (didn't notice dat during exam.....P)
so how to proceed in this question?
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5 Answers
1any option except 2.5
Reason- The formulae are valid for bulk(some amount of measurable mass). We can't tell exactly how many atoms have actually dissociated during the time interval.
1According to me..in question u have to consider the no. of moles instead of no of atoms..
They will never talk about 40 atoms...they are atoms not balls
1which formula??? i solved it in this way dat since in 1st order kinetics t half remains constant so 1st in d interval of 10 hours atoms left 20, in next interval of 10 hours atoms left 10 nd so on......
doing this u wil get 2.5 after 40 hours.....
Is dere any formula for it????