Question

Help me answer this chemistry question. thank you!

Answer 1

78.85

Step-by-step explanation:

To calculate the average atomic mass of the isotopes we use the given masses and abundances, as follows:

• Mass of Isotope 1 * Abundance of Isotope 1 + Mass of Isotope 2 * Abundance of Isotope 2 + ....

In other words:

• 78 amu * 75/100 + 81 amu * 15/100 + 82 amu * 10/100 = 78.85

So the answer is 78.85.