The probability disintegration per second of a nucleus in a given radio-active sample

Calculate the number of disintegrations per second of 1 g of a radioactive sample whose half-life is 1.4 xx 10^(16)s . The mass number of the sample is 238

The disintegration rate of a certain radioactive sample at any instant is 4750 disintegrations per minute. Five minutes later the rate becomes 2700 per minute. Calculate (a) decay constant and (b) half-life of the sample

The disintegration rate of a certain radioactive sample at any instant is 4750 disintegrations per minute. Five minutes later the rate becomes 2700 per minute. Calculate (a) decay constant and (b) half-life of the sample

The disintegration rate of a certain radioactive sample at any instant is 4750 disintegrations per minute. Five minutes later the rate becomes 2700 per minute. Calculate (a) decay constant and (b) half-life of the sample

A radioactive sample had an initial activity of 28 disintegrations per minute. 30 minutes later, its activity became 14 disintegrations per minute. How many atoms of the radioactive nuclide were present intially ?