Question

A sample rock is found to contain 100 grams of a parent isotope. How many grams of the parent isotope will remain after two half lives?

Answer 1

A half-life is an amount of time, specifically the amount of time for a substance to decrease by 1 half.

SO if you have 100 g of something, after 1 half-life you have 50g, after the next half-life, you have 25 g, etc.

Answer 2

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