Lithium has only two naturally occurring isotopes. The mass of lithium-6 is 6.01512 amu and the mass of lithium-7 is 7.01601 amu. Calculate the relative abundances of the two isotopes.

• A. % abundance Li-6 = 92.588%% abundance Li-7 = 7.412%
• B. % abundance Li-6 = 7.412%% abundance Li-7 = 92.588%
• C. % abundance Li-6 = 92.506%% abundance Li-7 = 7.494%
• D. % abundance Li-6 = 7.494%% abundance Li-7 = 92.506%

Answer: (D)