Question & Answer

Define atomic mass unit


An atomic mass unit (symbolized AMU or amu) is defined as precisely 1/12 the mass of an atom of carbon -12. 

"Have a doubt going on your head? Download Vedantu's Instant Doubt Solving App now and get all your doubts cleared by our experts."

The carbon -12 (C -12) atom has six protons and six neutrons in its nucleus. The AMU is used to express the relative masses of, and thereby differentiate between, various isotopes of elements.