Ions and Ionic Bonding

Atoms that lose their valence electrons to another atom, the valence electrons are transferred from one atom to another. This allows both atoms to become stable

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An ion is an atom or group of atoms that has an electric charge.

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When an atom loses an electron it loses a negative charge and becomes a positive ion. When an atom gains an electron, it gains a negative charge and becomes a negative ion

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Polyatomic ions: Ions that are made up of more than one type of atom
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Can have a positive or a negative charge

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Ionic Bonding: the attraction between
2 oppositely charged ions

Ionic bonds form as a result of the attraction between positive and negative ions
A compound that consists of positive and negative ions is called an ionic compound

◦ When Ionic compounds form, the ions come together in a way that balances out the charges on the ions. The chemical formula for a compound reflects this balance

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A subscript tells you the ratio of elements in the compounds
(eg) Na (+1) + Cl (-1) = NaCl (0)

◦ Ionic compounds are usually hard, brittle, crystals that have high melting points. When dissolved in water or melted, they conduct electricity
◦ Sodium Chloride Sodium Hydroxide

A crystal is an orderly, 3-D pattern of ions or atoms in a solid

◦ In an ionic compound every ion is attracted to ions of opposite charge that surround it.

◦ The pattern formed by the ions remains the same no matter what the size of the crystal

◦ When you heat a substance its energy increases, therefore the ions have enough energy to overcome(break) the bonds that join them, and it melts into a liquid Ibuprofen MP

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A solid ionic crystal will not conduct electricity, however, a melted or dissolved crystal will conduct

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Hydrogen has one valence electron, so it is placed above the alkali family even though it is a nonmetal and has different properties than the alkalis. It is very reactive