Chemistry 12:  We began with a discussion about Solubility, and when we do  precipitation reactions we exceed the solubility of one or both potential products.  Table 4 in our data booklet helps us determine which product will precipitate, using 0.1 M as the standard for being able to deem a salt as "Soluble".  Time was given for Unit 3 # 21-24, and to finish last day's assignment (U3 # 1-10, 18-20d).   Next, we set about determining the concentration of MgSO4 in Spotted lake, when evaporation causes the water to become saturated in this salt (and a few other sulphates as well). We completed the Precipitations WS Mini Lab, which is due next class.  Finally, we went through one Ksp problem - finding the concentration of Mg2+ ions in Milk of Magnesia.