Percentage of isotopes in 35/17 Cl and 37/17 Cl

Explanation:

Average atomic mass of Chlorine = 35.45 amu

The percentage of isotopes is the percentage abundance.

This is given by;

Average atomic mass = (Mass of isotope * Percentage abundance of 35/17 Cl) + (Mass of isotope * Percentage abundance 37/17 Cl)

Let percentage abundance of 35/17 Cl = x

Then percentage abundance of 37/17 Cl = 1 - x

Putting the values in the equation;

35.45 = (35 * x)   + (37 * (1-x))

35.45 = 35x + 37 - 37x

35.45 - 37 = 35x - 37x

- 1.55 = -2x

x = 1.55 / 2 = 0.775

Percentage abundance of 35/17 Cl = 0.775 * 100 = 77.5%

Percentage abundance of 37/17 Cl = (1 - 0.775) * 100 = 22.5%

2b2t

explanation:

2b2t