Question

An element with mass 490 grams decays by 28.6% per minute. How much of the

element is remaining after 16 minutes, to the nearest 10th of a gram?

Answer 1

The mass of element after decay at the rate of 28.6% is 2.2 grams

Explanation:

Given as :

The mass of element = 490 grams

The decay rate is 28.6 % per minute

The time period = 16 minutes

Let The mass of element after decay = m

Now,

The mass after T minutes = Initial mass of element ×
`(1-(Rate)/(100))^(T)`

The mass after T minutes = 490 grams ×
`(1-(28.6)/(100))^(16)`

Or, The mass after T minutes = 490 grams × 4.562 ×
`10^(-3)`

Or, The mass after T minutes = 2.235 grams

Hence The mass of element after decay at the rate of 28.6% is 2.2 grams Answer