Atoms of different elements have different numbers of protons, which determine the element's atomic number and identity. Additionally, the number of neutrons can vary within atoms of the same element, leading to the existence of different isotopes of that element. The combined number of protons and neutrons gives the atomic mass of the atom.
Thus, the key distinctions among atoms of different elements are:
- Protons: The number of protons defines the element (e.g., hydrogen has 1 proton, while carbon has 6).
- Neutrons: The number of neutrons can vary, creating isotopes (e.g., carbon-12 has 6 neutrons, while carbon-14 has 8 neutrons).
- Electrons: The number of electrons usually equals the number of protons in a neutral atom, affecting the atom's charge and reactivity.
In summary, different elements have different numbers of protons, and their neutrons, electrons, and atomic mass can also vary depending on isotopes and the element itself.