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mina [271]
3 years ago
15

Sodium-24, which is used to locate blood clots in the human circulatory system, has a half-life of 15.0 h . A sample of sodium-2

4 with an inital mass of 13.0 g was stored for 45.0 h . How many grams of sodium-24 are left in the sample after 45.0 h ?
Physics
1 answer:
Amanda [17]3 years ago
7 0

Answer:

0.3967mg of sodium-24 are left

Explanation:

If the half life of radioactive element (which is sodium-24 here) is T_{1/2}, then at the end of this time the number of atoms in the sample will become half i.e. 1/2 .

if the original amount of atoms is N°. The formula for calculating the remaining atoms (N) left in the sample after t half lives would be:

N=N^{o}  * (1/2)^{t}

Here, in this question,

Given amount of sodium-24 = N° = 13 grams

Half life of sodium-24 = t = 15

and Remaining amount of sodium after 45 hours = N = ?

Therefore, using the given Forumla:

N=\frac{13}{2^{15} }

N= 3.967*10^{-4} g\\ N=0.3967 mg

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