Question

Helium atom has a atomic mass 40 and two protons in its nucleus. How many neutron does it have?

Answer 1

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< Application of Concepts >


Well ,This is a hypothetical question .Generally Atomic mass of Helium is 4 amu.

I hope this question was Based on The Formula ,Atomic mass=Number of neutrons+Number of protons. 

Given ,Atomic mass of Helium =40

Number of protons=2 

Hence ,Number of neutrons=40-2=38

Number of Neutrons in the helium atom of mass 40 possessing 2 protons is 38 neutrons .

Answer 2

it have 40-2 = 38 neutrons