The helium atom has an atomic mass of 4 u and two protons in its nucleus. How many neutrons does it have?

Academic Chemistry NCERT Class 9

Atom mass of He = 4u.

Atom mass = no of protons + no of neutrons.

Therefore , 4 = 2 + no of neutrons

Therefore , No. of neutrons = 4 - 2 = 2

Helium atoms has 2 neutrons.

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Updated on: 14-Mar-2023

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