Question

HELP!!

There are four isotopes of lead and their relative abundance listed below. Use this information to calculate the approximate atomic mass of lead. Show all work clearly!!

82 protons, 122 neutrons, 1.4%82 protons, 125 neutrons, 22.1%82 protons, 124 neutrons, 24.1%82 protons, 126 neutrons, 52.4%

Answer 1

207.24.

Step-by-step explanation:

The mass numbers of the 4 isotopes are 82+ 122 = 204, 82 + 125 = 207,

82 + 124 = 206 and 208.

The approximate atomic mass is worked out by adding the products of their relative abundances and mass numbers:

0.014*204 + 0.221*207 + 0.241*206 + 0.524*208

= 207.24.