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A 32 gram sample of a substance that’s a by-product of fireworks has a k-value of 0.1368. Find the substance’s half-life, in days. Use formula

N=N0e-kt, t= time in days.
HELP PLS

User Nataliya
by
5.8k points

2 Answers

1 vote

Answer:

5.1

PLATO answer

Explanation:

User Bmdhacks
by
6.6k points
3 votes

Answer:

t=5.1 days

Explanation:

We know that the formula is:


N = N_0e^(-kt)

Where N is the amount of substance after a time t,
N_0 is the initial amount of substance, k is the rate of decrease, t is the time in days.


k=0.1368\\N_0 =32

We want to find the average life of the substance in days

The half-life of the substance is the time it takes for half the substance to disintegrate.

Then we equal N to 16 gr and solve the equation for t


16= 32e^(-0.1368t)


0.5= e^(-0.1368t)


ln(0.5)= ln(e^(-0.1368t))


ln(0.5)= -0.1368t


t= (ln(0.5))/(-0.1368)\\\\t=5.1\ days

User Pippobaudos
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