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A 500g sample of Ca-37 decays for 910ms. How much of the original sample remains?

User Docuemada
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1 Answer

13 votes

Answer:

15.6 g

Step-by-step explanation:

Given that;

Mass of original sample = No = 500g

mass of sample remaining at 910 ms = N = ?

time taken to decay= 910 ms

Half life of Ca-37 = 181 milliseconds

From;

N/No = (1/2)^t/t1/2

N/500 = (1/2)^910/181

N/500 = (1/2)^5

N/500 = 1/32

32 N = 500

N = 500/32

N = 15.6 g

User Gwennael Buchet
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