Question

a 23 gram sample of a substance thats a by-product of fireworks has a K-value of .13. whats the substances half life in days

Answer 1

5.3 is the right answer.

Explanation:

Answer 2

Given:
Initial mass, m₀ = 23 g
Decay constant, k = 0.13

Exponential decay obeys the equation

`m(t)=m_(0) e^(-kt)`
where t = time, days

For half life, the mass is m = m₀/2.
Therefore

`e^(-0.13t) = (1)/(2) \\ -0.13t = ln(0.5)\\t= (ln(0.5))/(-0.13) =5.33`

Answer: The half life is 5.33 days