Question

This exercise uses the radioactive decay model.

If 250 mg of a radioactive element decays to 180 mg in 60 hours, find the half-life of the element. (Round your answer to the nearest whole number.)

Answer 1

Formula:

Nt = N0 [(1 / 2) ^ (t / t(1/2) )

where Nt = current amount of radioactive substances.

N0 = Initial amount of radioactive substances.

t1/2 = half life of radioactive substances.

t = quantity of substances remains after the time t.

in this problem
Nt = 189 mg, N0 = 250 mg, , t = 60 hours

200 = 250 [ (1/2)^ (48 / t(1/2) ) ]

(1/2)^ (48 / t(1/2) ) = 200/250 = 0.8

48 / t(1/2) = Log ( with the base of 1/2 ) 0.8 = log 0.8 / log 0.5 = 0.32

t(1/2) = 48 /0.32 = 150

so the half life of the radioactive is 150 hours
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Answer 2

@hannahmarie620

Answer 3

that isn't right