You are given 230 grams of a substance with a half-life of 0.75 years. How much will remain after 3 years?

1 Answer
Feb 4, 2018

There is 1/16116 of the original amount, 14.375 g.

Explanation:

Each time a period of time goes by that is equal to the half-life, there will be only 1/2 of the previous amount of material remaining.

In this case, three years represents 3-: 0.75 = 43÷0.75=4 half-lives.

So, the amount that remains has been halved four times:

1/2 xx 1/2xx1/2xx1/2 = (1/2)^4 = 1/1612×12×12×12=(12)4=116

There is 1/16116 of the original amount, which is

230 xx 1/16 = 14.375230×116=14.375 g