Would you use the atomic number, mass number, or both to determine each of the following?
d. number of electrons in a neutral atom

Verified step by step guidance

1. Understand the concept of a neutral atom: A neutral atom has no overall charge, meaning the number of protons (positively charged particles) is equal to the number of electrons (negatively charged particles).
2. Recall that the atomic number represents the number of protons in an atom. Since a neutral atom has an equal number of electrons and protons, the atomic number also indicates the number of electrons.
3. Note that the mass number is the sum of protons and neutrons in the nucleus of an atom. It does not provide information about the number of electrons.
4. Conclude that only the atomic number is needed to determine the number of electrons in a neutral atom, as it directly corresponds to the number of protons, which equals the number of electrons in this case.
5. Avoid using the mass number for this determination, as it does not relate to the electron count in a neutral atom.

Key Concepts

Atomic Number

The atomic number is the number of protons in the nucleus of an atom, which uniquely identifies an element. In a neutral atom, the atomic number also indicates the number of electrons, as the positive charge of protons is balanced by the negative charge of electrons. Therefore, the atomic number is essential for determining the number of electrons in a neutral atom.

Mass Number

The mass number is the total number of protons and neutrons in an atom's nucleus. While it provides information about the atom's isotopes and overall mass, it does not directly indicate the number of electrons. Thus, the mass number is not necessary for determining the number of electrons in a neutral atom.

Neutral Atom

A neutral atom is one where the number of protons equals the number of electrons, resulting in no overall charge. This balance is crucial for understanding atomic structure and behavior in chemical reactions. When identifying the number of electrons in a neutral atom, the atomic number is the key factor, as it directly reflects the number of protons and, consequently, the number of electrons.