Use the data given in the following table to calculate the molar mass of naturally occurring argon isotopes:
Isotope | Isotopic molar mass | Abundance |
36Ar | 35.96755 gmol–1 | 0.337% |
38Ar | 37.96272 gmol–1 | 0.063% |
40Ar | 39.9624 gmol–1 | 99.600% |
Step 1:
Average atomic mass = Sumoftheproductsofmassesandnaturalabundaces100
Step 2:
Molar mass of argon =
= 39.947gmol–1
Hence, the molar mass of argon is 39.947 g/mol