What type of atoms generally form ionic or covalent bonds?

Answer 1

ionic bonds are formed when a metal atom ionizes (forms a cation) and a non metal atom ionizes (anion). The cation is positively charged because the metal loses electron and the anion is negatively charged because it gains electron. The positive cation and negative anion come together to form an ionic bond.

Covalent bonds are NON METALS that bond by sharing electrons. Covalent bonding is much more complex than ionic bonding. Generally only non metals form covalent bonds, although there are some exceptions where metals can form covalent bonds.

Answer 2

non-metals Generally, there are two reasons for this: 1. Elements strive to satisfy the "octet rule." 2. A covalent bond shares electrons in a much more even distribution, while an ionic bond is extremely one-sided. So it's likely that elements on the ends of the Periodic Table (e.g. Na or Cl) will basically lose or take on an extra electron at the expense of a formal charge in an ionic bond because it satisfies the octet rule. This is even possible for a +2 or -2 charge, but formal charges beyond that become too powerful to overcome with an ionic bond, so sharing is preferred. Carbon, for example, is right in the middle. It would require a formal charge of +4 to drop down to the Helium position or -4 to get up to the Neon position. Although the octets rule "always wins" when competing against a formal charge, a +4 or -4 is too much to overcome, ergo Carbon typically has four covalent bonds. (Incidentally, when this sort of thing tries to happen, it frequently results in a free radical.)