With symbols having their usual meanings, which one among the following is used as the standard for defining atomic mass unit?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. C-12.
The standard for defining the atomic mass unit (amu) is based on the carbon-12 (C-12) isotope.
One atomic mass unit is defined as one twelfth of the mass of a carbon-12 atom. This definition provides a standard reference for measuring the masses of other atoms and molecules. Carbon-12 is chosen because it is a stable isotope of carbon and is abundant in nature, making it a convenient reference point for atomic mass calculations.