Question

1. the atomic number indicates the number of ______. (choose 2) protons electrons neutrons atomic mass

Explanation:

The atomic number is defined as the number of protons in an atom's nucleus, which uniquely identifies an element. In a neutral atom, the number of electrons equals the number of protons, but electrons can vary in ions. Neutrons determine isotopes, not atomic number; atomic mass is the sum of protons and neutrons. The question asks for two correct choices, but only protons are definitively indicated by atomic number. However, if considering neutral atoms, electrons also match, but the standard definition prioritizes protons. Wait, the original selection in the image has protons and neutrons checked, which is incorrect—neutrons are not part of atomic number. The correct choices should be protons (always) and electrons (in neutral atoms). But per the question's instruction to choose 2, the standard correct pair is protons and electrons (for neutral atoms).

Answer:

protons, electrons