Answer:
The mass of heavier isotope is 345.6 amu.
Explanation:
Given data:
atomic wight of compound = 342.38 amu
lighter isotope mass = 340.91 amu
abundance of lighter isotope = 68.322%
mass of heavier isotope = ?
Solution:
average atomic mass = ( % age abundance of lighter isotope × its atomic mass) + (% age abundance of heavier isotope × its atomic mass) / 100
percentage of heavier isotope = 100- 68.322 = 31.678
Now we will put the values in formula.
342.38 = (68.322× 340.91) + (31.678 × X) / 100
342.38 = 23291.65302 + (31.678 × X) / 100
342.38 × 100 = 23291.65302 + (31.678 × X)
34238 -23291.65302 = (31.678 × X)
10946.35 / 31.678 = X
345.6 = X
The mass of heavier isotope is 345.6 amu.
