Nitrogen doesn't start out as a cation/anion, but it is in group 5A, so it has five valence electrons. To become stable (have a complete octet), it either has to lose five electrons or gain three. It is easier to gain three, so it gains three and becomes a 3- anion.
ion
A chromium ion is not neutral. By definition an ion is not neutral. All atoms belong to an isotope, but that has nothing to do with whether the atom is ionized or not.
In one atom of cobalt ion, the number of neutrons can vary based on the isotope. The most common isotope of cobalt is cobalt-59, which has 33 neutrons.
Nitrogen is a non metal and wants to gain (anion) three electrons making it N^-3 (Nitride ion).
An example of an atom is carbon (C), which has six protons. An example of an ion is a chloride ion (Cl-), which has gained an electron. An example of an isotope is carbon-14 (14C), which has 8 neutrons instead of the usual 6.
Neutral atom. An atom of nitrogen will also be an isotope of nitrogen.
This atom of Nitrogen with 7 protons, 7 neutrons, and 8 electrons is an isotope, specifically nitrogen-14. It is not an ion because it has an equal number of protons and electrons, so its charge is neutral. It is also not an average atom, as it has a specific number of protons and neutrons that define it as a particular isotope.
N-14 is the most common isotope of nitrogen atom and it has 7 protons, 7 neutrons
An alumimium atom is electrically neutral and it is an isotope of aluminum.
Helium is a neutral atom that has several isotopes and can become an ion.
This is not an atom. This is an ion. This is Na+ ion.
ion
When a nitrogen atom gains an electron, it becomes a nitride ion (N^{3-}) with a (3-) charge.
A chromium ion is not neutral. By definition an ion is not neutral. All atoms belong to an isotope, but that has nothing to do with whether the atom is ionized or not.
You call it an ion of that isotope. Let's use carbon-14 for example. If a carbon-14 atom gains/loses an electron, you simply call it a "carbon-14 ion".
they all have the same element with the same number
In one atom of cobalt ion, the number of neutrons can vary based on the isotope. The most common isotope of cobalt is cobalt-59, which has 33 neutrons.