Question

which of the following is correct about an atoms atomic number? * (0.5 points)
the atomic number is equal to the number of neutrons in the atom
the atomic number is equal to the number of protons plus the number of neutrons in an atom
the atomic number is equal to the number of protons in an atom
the atomic number is equal to the number of electrons in the atom
4
which of the following is true about an atoms mass number? * (0.5 points)
the mass number is the number of protons plus the number of electrons
the mass number is the number of protons plus the number of neutrons plus the number of electrons in the atom
the mass number is the number of neutrons plus the number of electrons
the mass number is the number of protons plus the number of neutrons

Explanation:

The atomic number of an atom is defined as the number of protons in its nucleus. The mass number is the sum of the number of protons and neutrons in the nucleus. Electrons have negligible mass compared to protons and neutrons and are not included in the mass - number calculation.

Answer:

The atomic number is equal to the number of protons in an atom
The mass number is the number of protons plus the number of neutrons