Question 1134804
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<pre>
According to the periodic table, the average mass of one mole of chlorine is 35.453 grams. 

Let x be the fraction of the chlorine that is number 35. 1  -  x is the fraction that is number 37. 


34.9689 * x + 36.9659 * (1  -  x) = 34.9689 * x + 36.9659  -  36.9659 * x 

34.9689 * x + 36.9659  -  36.9659 * x = 35.453 

1.997 * x = 1.5359 

x = 1.5359 ÷ 1.997 


The decimal fraction is approximately 0.769. This means 76.9% is 35 Cl and 23.1% is 37 Cl. I hope this is helpful for you.
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