Question

11/22 what is the atomic number? the number of atoms in a molecule the number of electrons in an atom’s nucleus the number of protons in an atom’s nucleus the number of neutrons in an atom’s nucleus

Explanation:

The atomic number of an element is defined as the number of protons in the nucleus of an atom of that element. It determines the identity of the element. Electrons are outside the nucleus, number of atoms in a molecule is a different concept, and neutrons do not define the atomic number.

Answer:

The number of protons in an atom’s nucleus