1. Aim: How can we determine the amount of solute in a solution? Do Now: 1.Take out a calculator and reference tables. 2.What are the factors that can change the solubility of a compound in a solution?

2. How can we tell the amount of solute a solution can hold? Reference Table G shows solubility curves for several ionic salts. The curve shows the number of grams of each substance that can be dissolved in 100g of water between 0°C and 100°C. Most lines show that solubility increases as temperature increases. The three exceptions are _____________, __________, and __________ which are all gases.

3. Reading the solubility curves The curve shows the maximum amount of solute that will dissolve at a specific temperature in 100g of water. This is when the solution is known to be saturated. Points below the line are known as unsaturated. Points above the line are known as supersaturated. This is a temporary condition that occurs when the solution is cooled. These solutions are unstable. The only way to make a supersaturated solution is to cool a saturated solution in which there are no crystals or impurities, such as dust, present.

4. Examples: How many grams of the compound KCl must be dissolved in 100g of water to make a saturated solution at 60°C? _______________ How many grams of the compound SO 2 must be added to 100g of water at 20°C to make a saturated solution? ____________________ How many grams of the compound KNO 3 must be added to 200g of water at 70°C to make a saturated solution? _____________________ How many grams of HCl must be added to 50g of water at 45°C to make a saturated solution? _______________________

5. Making specific solutions To make a solution with a specific molarity, we must find the gram formula mass, and add it to 1liter of solvent (usually water). The following steps are used: 1.Determine the number of moles of solute needed by using the formula: moles = MV = molarity x liters of solution 2. Convert moles to grams by finding the gram formula mass and then multiplying by the number of moles given.

6. Example: What mass of sodium carbonate is required to prepare 2.00L of a 0.250M Na 2 CO 3 solution?

7. Activity/Homework # Review Book page 123 – Copy #13-23. Copy and answer the questions you were given.