Question

You start with 4800 grams uranium - 238. It's radioactive and goes

through alpha decay. How many grams remain after 7 half-lives.

Answer 1

37.5g

Step-by-step explanation:

The half-life is the time taken for a radioactive substance to decay to half its original composition;

Original composition here is = 4800g of U-238

How many grams remain after 7 half-lives;

After each life, the uranium reduces by half;

Amount remaining = 4800 x
`((1)/(2))^7`

= 37.5g

After 7 half lives, 37.5g of the original sample will remain.