The element carbon has two naturally occurring isotopes. The isotopic masses and abundances of these isotopes are shown in the table.

Question

IsotopeIsotopic mass (u)Abundance (%)
12C	12.00	98.93
13C	13.00	1.07	Calculate the average atomic mass of carbon to two digits after the decimal point.

Calculate the average atomic mass of carbon to two digits after the decimal point.

average atomic mass =

Answer 1

(0.9893 x 12.00) + (0.0107 x 13.00) = 11.8716 + 0.1391 = 12.01 = average atomic mass of carbon