MCQ
Modern atomic mass scale is based on the mass of:
  • A
    H −1
  • B
    C −12
  • C
    C −14
  • D
    C −16

Answer

  1. C −12

Explanation:

Modern atomic weight scale is based on C −12.

The standard unit for expressing the mass of atom is amu (atomic mass unit).

It is equal to $\frac{1}{12}$ of the mass of an atom of carbon -12 equal to 1.6605 × 10−19g.

Amu is also called as avogram.

Avogram is a unit of mass and weight equal to one gram divided by the Avogadro's number.

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