Chemical Kinetics Question 344
Question: If half-life of a substance is 5 yrs, then the total amount of substance left after 15 years, when initial amount is 64 grams is
Options:
A) 16g
B) 2g
C) 32g
D) 8g
Show Answer
Answer:
Correct Answer: D
Solution:
[d] $ {t_{1/2}}=5 $ years, T= 15 years hence total number of half life periods $ =\frac{15}{5}=3 $
$ \therefore Amountleft=\frac{64}{{{(2)}^{3}}}=8g $