3 years ago

Hello guys, plz help me with this question ASAP! Plz show the working, THANK YOU BROTHER

Mathematics

1 answer:

RoseWind [281]3 years ago

8 0

Answer:

5.5 min

Step-by-step explanation:

At time t=0 you have 72 grams

at time t = 22 min you have 4.5 grams.

Now

4.5/72 = (1/2)^(t/half-life)

and t=22, so

4.5/72 = (1/2)^(22/half-life)

taking log of both sides:

log(4.5/72)=(22/half-life)log(1/2)

solving for half-life gives half-life = 11/2 = 5.5min

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