A radioactive isotope has initial activity of `28` dpm Its activity is reduced to `14` dpm after half an hour. The initial number of nuclide in sample was:A. `200`B. `400`C. `600`D. `1211`

A radioactive isotope has initial activity of `28` dpm Its activity is

1.	A radioactive isotope has initial activity of `28` dpm Its activity is reduced to `14` dpm after half an hour. The initial number of nuclide in sample was:A. `200`B. `400`C. `600`D. `1211`
Answer» Correct Answer - `(d)` Rate `= lambda N`, Also `t = (2.303)/(lambda) log ((r_(0))/(r))`, `:. 30 = (2.303)/(lambda) log ((28)/(14))` or `lambda = (2.303)/(30) xx 0.3010`, No `28 = (2.303xx0.3010)/(30) xx N` `:. N = 1211` atoms

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A radioactive isotope has initial activity of `28` dpm Its activity is reduced to `14` dpm after half an hour. The initial number of nuclide in sample was:A. `200`B. `400`C. `600`D. `1211`

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