Question

Define Atomic mass unit .​

Answer 1

A unit of mass for expressing masses of atoms, molecules, or nuclear particles equal to ¹/₁₂ the mass of a single atom of the most abundant carbon isotope 12C. — called also dalton.

Answer 2

The dalton or unified atomic mass unit is a unit of mass widely used in physics and chemistry. It is defined as 1⁄12 of the mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state and at rest. The atomic mass constant, denoted mᵤ is defined identically, giving mᵤ = m/12 = 1 Da.