An element has two isotopes, X and Y, with mass numbers of 52.0 and 53.0 respectively. The relative atomic mass is 52.2. What is the percentage abundance of isotope X?

• A. 70%
• B. 20%
• C. 50%
• D. 80%

Answer: (D)

Verified step by step guidance

1. Understand that the relative atomic mass is a weighted average of the isotopes' masses based on their abundances.
2. Let the percentage abundance of isotope X be represented by \( x \) and the percentage abundance of isotope Y be \( 100 - x \).
3. Set up the equation for the relative atomic mass: \( 52.0 \times \frac{x}{100} + 53.0 \times \frac{100 - x}{100} = 52.2 \).
4. Simplify the equation: \( 52x + 53(100 - x) = 5220 \).
5. Solve for \( x \) to find the percentage abundance of isotope X.