Question

the atomic number indicates
a the number of neutrons in a nucleus
b the total number of neutrons and protons in a nucleus
c the number of protons in a neutral atom
d the number of atoms in 1 g of an element

Explanation:

The atomic number is defined as the number of protons in the nucleus of an atom. In a neutral atom, the number of protons equals the number of electrons.

• Option A: The number of neutrons is not indicated by the atomic number.
• Option B: The total number of neutrons and protons is the mass number.
• Option C: Correct as the atomic number is the number of protons in a neutral atom.
• Option D: The number of atoms in 1g of an element is related to molar mass and Avogadro's number, not the atomic number.

Answer:

C. the number of protons in a neutral atom