ECAT Engineering Exams Quizzes MCQs Quizzes ECAT Engineering Entry Test 2017 Chemistry Basic Concepts 2

Question:
Many elements have fractional atomic masses. The reason is that

Option A):
Atomic masses are average masses of isotopes
Option B):
The mass of atom is itself fractional
Option C):
Atomic masses are average masses of isotopes which are proportional to their relative abundance
Option D):
Atomic masses are average masses of isobars

Correct Answer is Option C):
Atomic masses are average masses of isotopes which are proportional to their relative abundance