Atomic numbers vs mass numbers: The mass number (A) of an atom equals what count of subatomic particles? Relate A to the composition of the nucleus (protons and neutrons). Choose the correct option.

Q: Atomic numbers vs mass numbers: The mass number (A) of an atom equals what count of subatomic particles? Relate A to the composition of the nucleus (protons and neutrons). Choose the correct option.

Concept/Approach Mass number A = total number of nucleons = protons + neutrons. Atomic number Z = protons only. Final Answer The number of nucleons

Difficulty: Easy

The number of protons
The number of protons and electrons
The number of nucleons
The number of neutrons

Correct Answer: The number of nucleons

Explanation:

Concept/Approach
Mass number A = total number of nucleons = protons + neutrons. Atomic number Z = protons only.

Final Answer
The number of nucleons

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