An element X has isotopic masses of 6 and 7. if the relative abundance is 1 to 12.5 respectively, what is the relative atomic mass of X?
Answer Details
Isotopes are atoms of the same element with different numbers of neutrons, and they have the same atomic number but different mass numbers. The relative abundance of an isotope is the proportion of that isotope in a sample of the element.
In this question, element X has two isotopes with mass numbers of 6 and 7, and their relative abundances are given as 1 and 12.5, respectively. The relative atomic mass (RAM) of X can be calculated using the following formula:
RAM = (mass of isotope 1 x abundance of isotope 1 + mass of isotope 2 x abundance of isotope 2) / total abundance
Plugging in the given values, we get:
RAM = (6 x 1 + 7 x 12.5) / (1 + 12.5)
Simplifying the expression, we get:
RAM = (6 + 87.5) / 13.5
RAM = 93.5 / 13.5
RAM ≈ 6.93
Therefore, the relative atomic mass of X is approximately 6.93. Hence, the correct option is "6.9".