Final answer:
The difference between an atom and an ion is that an atom is electrically neutral with equal numbers of protons and electrons, while an ion has an imbalance in the number of protons and electrons, giving it a net charge, either positive (cation) or negative (anion).
Step-by-step explanation:
Difference Between Atom and Ion
The difference between an atom and an ion lies in the number of electrons. An atom is the fundamental unit of matter and is composed of a nucleus containing protons and neutrons, with electrons orbiting this nucleus. Atoms are electrically neutral because they contain an equal number of protons and electrons, which means their positive and negative charges cancel out. On the other hand, an ion is an atom that has either lost or gained electrons, giving it a net positive or negative charge. When an atom loses one or more electrons, it becomes a cation (positively charged), and when an atom gains electrons, it becomes an anion (negatively charged). The number of protons in an atom determines the element, whereas the charge of an ion indicates its ability to combine with other ions to form compounds.
Atoms vs Ions
- Atoms: Have an equal number of protons and electrons, thus neutral in charge.
- Ions: Have an unequal number of protons and electrons, thus have a net charge (positive or negative).
Atoms that vary in the number of neutrons found in their nuclei are called isotopes, not ions. Isotopes have the same number of protons and electrons but differ in the number of neutrons they contain, which affects their mass but not their charge.