An element X has two isotopes, \(^{20} _{10}X\) and \(^{22} _{10}X\),
present in the ratio 1:3. The relative atomic mass of X would be?
A
20.5
B
21.0
C
21.5
D
22.0
E
22.5
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
The relative atomic mass will be [(20 * 1) + (3 * 22)] / (4)
(86)/(4) = (43)/(2) = 21.5
Source: WAEC / JAMB / NECO Classroom Archive (Record #14067)