Disintegrations

A sample of ²¹⁰A which is emitter with T_1/2 = 138 days is observed by a student to have 2000 disintegrations per second. The mass of ²¹⁰A sample is

1.) 1.0 Ã— 10^-11 kg

2. ) 1.7 Ã— 10^-11kg

3). 1.7 Ã— 10^-11gm

4.) 1.2 Ã— 10^-11gm

2 Answers

Hint: FInd the value of lamda (or k whatever you want to call it)

Then what is the rate of disintegration? (for a first order reaction?) something like k.[A] ??

Now solve

Yes Nishant Sir
I got it
Thanks

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