An element with mass 140 grams decays by 21.6% per minute. How much of the element is remaining after 20 minutes, to the nearest
2 answers:
Answer:The mass of the remaining element = 1.1 grams .
Step-by-step explanation:
Exponential equation of decay : ... (i), where A = initial value , r= rate of decay in decimal , x= time.
As per given : Initial mass : A= 140 grams
Rate of decay : r= 21.6% per minute= 0.216 per minute.
x= 20 minutes
Substitute values in (i) , we get
Hence, the mass of the remaining element = 1.1 grams .
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Its is surprising that no one attempted this question for over a week.
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Have a good day.
