Hypothetical element A has three stable isotopes. The first isotope has a mass of 35.01 amu and an abundance of 35.00%. The second isotope has a mass of 36.01 amu and an abundance of 15.00%. The third isotope has a mass of 37.02 amu and an abundance of 50.00%. What is the atomic mass of element A

36.16 amu

Explanation:

From the question given above, the following data were obtained:

1st Isotope:

Mass of 1st isotope = 35.01 amu

Abundance of 1st isotope = 35%

2nd isotope:

Mass of 2nd isotope = 36.01 amu

Abundance of 2nd isotope = 15%

3rd isotope:

Mass of 3rd isotope = 37.02 amu

Abundance of 3rd isotope = 50%

Atomic mass of element A =?

The atomic mass of element A can be obtained as follow:

Atomic mass = [(mass of 1st × Abundance)/100] + [(mass of 2nd × Abundance)/100] + [(mass of 3rd × Abundance)/100]

= [(35.01 × 35)/100] + [(36.01 × 15)/100] + [(37.02 × 50)/100]

= 12.25 + 5.40 + 18.51

= 36.16 amu

Thus, the atomic mass of element A is 36.16 amu

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.