Final answer:
Atoms of different elements differ in their atomic number (number of protons in the nucleus), the number of neutrons (resulting in isotopes), and the electron configuration which determines the element's chemical properties.
Step-by-step explanation:
Atoms of different elements differ primarily in terms of their atomic number, which is fundamentally the number of protons in their nucleus. This is the defining characteristic of an element. For instance, hydrogen has an atomic number of 1, implying it has a single proton, while helium has an atomic number of 2, indicating it has two protons.
Furthermore, differing numbers of neutrons create isotopes of the same element. These isotopes have the same atomic number but different atomic weights. For example, carbon-12 and carbon-14 are both isotopes of carbon. They have the same number of protons (6), but carbon-14 has two more neutrons.
Also, atoms of different elements show variation in their electron configuration. The atomic structure and the number of electrons in outer shells determines the chemical properties of an element.
Learn more about Atomic differences