To predict characteristics of ions, we can look at the periodic table. First of all, we don't need to worry about the non-metals, because we know that they form covalent bonds by sharing electrons. So we look at a bond with a metal and a non-metal in which they will try to become the nearest noble gas.
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Naturally, when drawing out a diagram of the molecule, we try to minimize positive-positive and negative-negative bonds and try to maximize positive-negative bonds because bonds. We do this because atoms try to bond in a way in which less energy is used. If atoms have to fight a charge repulsion, more energy is needed. We also know that size of the ionic radius increases as you go down and as you go across the periodic table. this is important because size determines structure and stability of the compound, and greatly effects the properties of the aqueous solution and the biological effects. |
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