Chemistry
Grade-8
Easy
Question
The atomic mass of an atom that has 12 protons, 12 electrons and 12 neutrons is:
- 36
- 24
- 12
- 40
Hint:
Atomic mass in the mass of the nucleus.
The correct answer is: 24
The atomic mass = sum of protons and neutrons
=12+12
=24u
The atomic mass of an element is the average mass of the element's atoms measured in atomic mass units (amu, aka Daltons, D).
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