Question

The relative abundances of 12C and 13C are respectively 98.892 and 1.108. If the atomic masses of
12C and 13C are 12 u and 13.00335 u, respectively, calculate the average atomic mass of carbon.​

Answer 1

12.01108 Units

C₁₂ Abundance = 98.892  

C₁₂ Mass = 12 U

C₁₃ Abundance = 1.108

C₁₃ Mass = 13.00335 U

Average =  12 ˣ 98.892/100 +13 ˣ1.108/100

= 12.01108 Units