6. how is the number of neutrons in the nucleus of an atom calculated?

By substracting the atomic mass by the number of protons.

here is an example sodium's atomic mass is 23,
it is given that the number of protons is 11. Find the number of neutrons.

easy substract 23 from 11. the answer is 12 neutrons.

For the answer to the question above, you must first calculate the no. of Neutrons. Then, subtract the atomic number from the atomic weight. The result of that is the number of a neutron.The atomic number is the number of protons. The atomic weight consists of the number of protons plus the number of neutrons. I hope my answer helped you

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