1. Solutions IB Chemistry Pages 121-122

2. A solution is a homogeneous mixture of 2 or more substances. It is made of a solvent and a solute.

3.  SOLUTE – the part of a solution that is being dissolved (usually the lesser amount)  SOLVENT – the part of a solution that dissolves the solute (usually the greater amount)  Solute + Solvent = Solution SoluteSolventExample solidsolid Metal alloys solidliquid Kool aid liquidliquid Alcoholic drinks gasliquidPepsi gasgasair

4. Concentration of Solute The amount of solute in a solution is given by its concentration. Molarity (M) = moles solute liters of solution

5. Concentration  If something is concentrated it has more moles/grams of solute per amount of solvent. Ex: 12 M HCl Ex: 12 M HCl  If something is dilute it has less moles/grams of solute per amount of solvent Ex: 0.10 M HCl Ex: 0.10 M HCl

6. PROBLEM: Dissolve 5.00 g of NiCl 2 6 H 2 O in enough water to make 250 mL of solution. Calculate the Molarity. Step 1: Calculate moles of NiCl 2 6H 2 O Step 2: Calculate Molarity NiCl 2 6 H 2 O [NiCl 2 6 H 2 O ] = 0.0841 M

7. Step 1: Change mL to L. 250 mL * 1L/1000mL = 0.250 L Step 2: Calculate. Moles = (0.0500 mol/L) (0.250 L) = 0.0125 moles Step 3: Convert moles to grams. (0.0125 mol)(90.00 g/mol) = 1.13 g moles = MV What mass of oxalic acid, H 2 C 2 O 4, is required to make 250. mL of a 0.0500 M solution?

8. IB Note  Square brackets [0.60] means  0.60 M or  0.60 mol/L or  0.60 mol dm -3 This is what IB uses!

9. Homework  Page 135 # 3.92, 3.94 a,b, 3.96, 3.97