As noted earlier, there are three kinds of chemical bonds: ionic-these bonds form between ions, and usually bond a metallic element to a nonmetallic one; covalent--these bonds form between atoms which have not become ions and usually occur between nonmetals metallic---these form between atoms of metals In an ionic bond, a metal atom completely transfers an electron (or 2, or 3) to another atom or group of atoms. The metal atom then becomes a positive ion. The atom (or group of atoms) to which the electron is transferred becomes negatively charged. The positive and negative ions then attract each other, forming an ionic compound. We showed a simplified version of this a few pages back in the context of a discussion of sodium chloride:     You can look upon this as sort of like a whale being harpooned...the sodium shoots out an electron to the chlorine atom, and then the harpooned whale (the chloride ion), is reeled in due to the electronic attraction between the two ions. In a covalent bond, electrons are shared as opposed to transferred...they are handed back and forth between the atoms that are sharing them, and this causes the atoms to attract each other and form a molecule. I realize that this doesn't sound too convincing just yet...but be patient...covalent bonding is a little tougher to understand than ionic bonding and we are only giving you some of the facts so far. In metallic bonding, the electrons act like a kind of oatmeal, in which the nuclei (the raisins) float. This kind of bonding is the reason that metals conduct electricity so readily, but it will not concern us after this.

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