180 * (1/2)^(1325/265) = 5.625 g
Note that 1325 = 5*265, so that's 5 half-lives
so, 1/2^5 = 1/32 will remain
180/32 = 45/8
You have 180 g of a radioactive substance. It has a half-life of 265 years. After 1,325 years, what mass remains?
1 answer
1 answer