How do atoms of copper differ from atoms of aluminum?

• A. Atoms of copper have more protons in their nuclei than atoms of aluminum.
• B. Atoms of copper and aluminum have the same number of neutrons.
• C. Atoms of copper and aluminum have identical atomic numbers.
• D. Atoms of copper have fewer electrons than atoms of aluminum.

Answer: (A)

Verified step by step guidance

1. Recall that the atomic number of an element is the number of protons in its nucleus, which uniquely identifies the element.
2. Look up the atomic numbers of copper and aluminum: copper has an atomic number of 29, and aluminum has an atomic number of 13.
3. Since copper has more protons (29) than aluminum (13), atoms of copper differ by having more protons in their nuclei.
4. Understand that the number of neutrons can vary among isotopes of the same element, so atoms of copper and aluminum generally do not have the same number of neutrons.
5. Recognize that atoms of copper and aluminum do not have identical atomic numbers, and since the number of electrons equals the number of protons in a neutral atom, copper atoms have more electrons, not fewer, than aluminum atoms.