Question

quiz #2 begin date: 10/20/2025 12:01:00 am due date: 10/26/2025 11:59:00 pm end date: 10/26 problem 23 two versions of an element with different numbers of neutrons are called isotopes. electron pairs. re-runs. ions. molecules. 1 submission(s) remaining hints: feedback:

Explanation:

• Isotopes: Atoms of the same element (same number of protons) but different numbers of neutrons. For example, carbon - 12 (6 protons and 6 neutrons) and carbon - 14 (6 protons and 8 neutrons) are isotopes of carbon.
• Electron pairs: Refers to two electrons in an orbital (like in covalent bonding where electron pairs are shared, or in Lewis structures where lone pairs of electrons are shown around atoms). This has nothing to do with the number of neutrons in an element's atoms.
• Re - runs: This is not a term related to atomic structure or the number of neutrons in an element. It is more of a general term (e.g., re - running a process) and not relevant here.
• Ions: Atoms that have gained or lost electrons. For example, a sodium atom (Na) can lose an electron to become a sodium ion (\(Na^{+}\)). The change is in the electron count, not the neutron count.
• Molecules: Combinations of two or more atoms (can be of the same or different elements) held together by chemical bonds (e.g., \(O_{2}\) is a molecule of oxygen). This is about the combination of atoms, not the neutron - related variation within an element.

Answer:

isotopes.