Question

The atomic masses of 35-Cl (75.53 percent) and 37-Cl (24.47 percent) are 34.968 amu and 36.956 amu, respectively. Calculate the average atomic mass of chlorine. The percentages in parentheses denote the relative abundances

Answer 1

Answer:

35.45 amu is the average atomic mass of chlorine.

Explanation:

The average atomic mass is given :

$\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i$

Atomic mass of 35-Cl = 34.968 amu

Percentage abundance of 35-Cl = 75.53%

Fractional abundance of 35-Cl = 0.7553

Atomic mass of 37-Cl = 36.956 amu

Percentage abundance of 37-Cl = 24.47%

Fractional abundance of 37-Cl = 0.2447

Average atomic mass of chlorine:

$=34.968 amu\times 0.7553+36.956 amu\times 0.2447=35.45 amu$

35.45 amu is the average atomic mass of chlorine.