Question

1. select the answer from the menu.

the natural isotope abundance of copper is shown on the table
natural isotope abundance

isotope	percent abundance
copper - 63	69.2%
copper - 65	30.8%

the average atomic mass of copper is - choose the correct answer - amu
clear all
choose the correct answer
63.1
63.6
64.0
64.4

Explanation:

Step1: Convert percentages to decimals

Copper - 63 has an abundance of $69.2\%=0.692$, copper - 65 has an abundance of $30.8\% = 0.308$.

Step2: Calculate the contribution of each isotope

The atomic mass of copper - 63 is 63 amu and of copper - 65 is 65 amu. The contribution of copper - 63 is $63\times0.692 = 43.596$ amu, and the contribution of copper - 65 is $65\times0.308=20.02$ amu.

Step3: Calculate the average atomic mass

Add the contributions of the two isotopes: $43.596 + 20.02=63.616\approx63.6$ amu.

Answer:

63.6