# Technetium 99 is used for brain scans. If a laboratory receives a shipment of 200 g of this isotope, how much will remain after 24 hours? The half life of Technetium 99 is 6 hours.

##### 2 Answers

Apr 24, 2018

12.5 g

#### Explanation:

The basic formula for half life equations is

A= amount remaining

P= original amount

t= elapsed time

h=half life time

so just plug in your amounts

P=200

t=24

h=6

when you put it into a calculator, you get 12.5 grams

:)

Apr 24, 2018

Consider that radioactive decay follows first order kinetics. Thus, recall,

Now, let's derive the rate constant,

Given

of technetium-99 will remain of the shipment.