Tuesday May 12 Objective: Quiz on solutions and dilutions Checkpoint: – How many grams of KOH do you need to make mL of a 0.25 M solution? – You have 100 mL of a 2.0 M solution of KOH. How many mL of this solution do you need to dilute to make 10 mL of a 0.2 M solution of KOH? Homework: - (take reading notes) due Wed/Thurs

How many grams of KOH do you need to make mL of a 0.25 M solution? mL  L M 0.25 M = 0.5 L = mol grams  mol mol x g 1 mol 7.01 g = x X = (0.25 M)(0.5 M) 0.5 L

You have 100 mL of a 2.0 M solution of KOH. How many mL of this solution do you need to dilute to make 10 mL of a 0.2 M solution of KOH? M1M1 V1V1 (2.0 M) M2M2 V2V2 (V1)(V1) =(0.2 M)(10 mL) (2.0 M) V 1 = 1 mL