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IRINA_888 [86]
4 years ago
10

Calcium-51 has a half-life of 4.5 days. Only 0.75 gram remains of a sample that was initially 12 grams. How old is the sample of

calcium-51? 4.5 days 9.0 days 13.5 days 18 days
Physics
2 answers:
marysya [2.9K]4 years ago
9 0
 The answer is 18 grams.

12 grams.divided by 2= 6 grams divided by 2=3 gramsdivided by 2= 1.5 gramsdivided by 2= 0.75 gram 
4 times it is being halfed4.5 day it takes to lose the half
                                                     So, (4 x 4.5 days) = 18 days .
Read 
irina [24]4 years ago
7 0

18 grams!!!!!!!!!!!!!!!!!!!!!!!!

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swat32

Answer:

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