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sodium-24 has a half life of 15 hours. How much sodium-24 will remain in an 18.0 g sample after 60 hours?

sodium24 has a half life of 15 hours How much sodium24 will remain in an 180 g sample after 60 hours class=

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Neetoo

Answer:

Sample remain after 60 hours 1.125 g.

Explanation:

Given data:

Half life of sodium-24 = 15 hours

Total amount of sample = 18 g

Sample remain after 60 hours = ?

Solution:

Number of half lives = T elapsed / half life

Number of half lives = 60 hours/15 hours

Number of half lives =  4

At time zero = 18 g

At first half life = 18 g/2 = 9 g

At second half life = 9 g/ 2= 4.5 g

At third half life = 4.5 g/2 = 2.25 g

At 4th half life = 2.25 g/2 = 1.125 g

Sample remain after 60 hours 1.125 g.