# How much grams of a substance will be left after 2 hours if its half life is 15 minutes?

##### 1 Answer

Apr 30, 2016

#### Answer:

#### Explanation:

Let the initial mass be M g,

Half life period is 15 min

In 2 hrs or 120 min there will be

For each half life the mass is halved, so after 2 hrs i.e. after 8 half life periods the mass will be