Average atomic mass and applications of isotopes — task. Chemistry CBSE Live product, Class 9 (2025-26).

Identify the correct answer:

1. The formula to find average atomic mass is

\frac{\sum (Mass of isotopes \times % Natural abundance)}{100}

\frac{\sum (Mass of isotopes \times 100)}{% Natural abundance}

\frac{(% Natureal abundance \times 100)}{\sum (Mass of isotopes)}

d. $\frac{\sum (Mass of isotopes)}{100}$

2. Which isotope is commonly used as nuclear fuel in reactors?

Carbon-14
Iodine-131
Uranium-235
Carbon-12

Did you find an error?

2. Average atomic mass and applications of isotopes