The half-life of a radioactive kind of lanthanum is 93 minutes. How much will be left after 279 minutes, if you start with 2,064 grams of it?

Question

Its about half-life and you have to use a certain formula.

 

Answer 1

A = a₀(0.5)^t/h, where a₀ = initial amount, t = time, h = half life.

 

A = 2064(0.5)^279/93

A = 2064(0.5)³

A = 2064(0.125)

A = 258

 

After 279 minutes 258 grams remain.