ionic equations and precipitation

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 - amount of solute per volume of solvent - e.g. g / L
 - relative terms - "concentrated" or "dilute"
 - mg / L = ppm = $\mu$g / g
 - amount of solute per volume of solvent - e.g. g / L
 - relative terms - "concentrated" or "dilute"
 - mg / L = ppm = $\mu$g / g

+
+## Molarity
+- special concentration unit in mol / L (abbbreviation M)
+$$c={n \over v}$$
+
+| Quantity               | Symbol  | Unit          |
+| ---------------------- | ------- | ------------- |
+| molar mass             | $M$     | g / mol       |
+| molar concentration    | $c$     | mol / L ($M$) |
+| specific heat capacity | $c$     | J / g / K     |
+
+## Precipitation reactions
+Ions in solution combine to form a new compound.
+Precipitation reactions happen when water cannot dissociate ionic lattice structure.
+Precipitate (product):
+- generally insoluble in water
+- forms as solid particles that settle
+- forms from compounds insoluble in water
+
+All group 1 ions are soluble.
+
+**Ions swap between reactants**
+
+## Ionic equations
+
+Used when a salt (ionic) dissolves into constituent ions.
+"Spectator" ions - ions that do not dissolve or precipitate in reaction. **Not** included in equations.