Question

Francium has a decay rate of 50% every 22 minutes. How much of an initial amount of 4.8 grams would be left after 88 minutes?

t=88/22=4A=Aoe^-kt

Answer 1

0.65g

Explanation:

Decay rate = 50%

Decay rate = 0.5

`A = Aoe {}^( - kt)`

where Ao = initial amount at start, k = rate of decay or growth, t = time, e = euler's number and A = value at time 't'

Ao = 4.8

t = 88/44 = 4

k = 0.5

substitute these values in the equation

`A = 4.8e {}^( - 0.5 * 4)`

`A = 0.6496`

`A = 0.65 \: (2dp)`