Calculate the atomic mass of gallium if gallium has 2 naturally occurring isotopes with the following masses and natural abundances: Ga-69 68.9256 amu 60.11% Ga-71 70.9247 amu 39.89%?

69.7 amu

Explanation:

To get the atomic mass of Gallium, we use the relative abundance of the isotopes.

This is used as follows:

[60.11/100 * 68.9256] + [39.89/100 * 70.9247]

= 41.43117816 + 28.29186283 = 69.72304093 amu