Answer : The correct option is, (C) 51.996 amu
Explanation :
Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.
Formula used to calculate average atomic mass follows:
As we are given that,
Mass of = 49.946044 amu
Percentage abundance of = 4.345 %
Fractional abundance of = 0.04345
Mass of = 51.940508 amu
Percentage abundance of = 83.789 %
Fractional abundance of = 0.83789
Mass of = 52.940649 amu
Percentage abundance of = 9.501 %
Fractional abundance of = 0.09501
Mass of = 53.93880 amu
Percentage abundance of = 2.365 %
Fractional abundance of = 0.02365
Now put all the given values in above formula, we get:
Therefore, the atomic weight of the element is, 51.996 amu