Molarity M M moles of solute Liters of

Molarity (M) � M = moles of solute / Liters of Solution What is the molarity of a solution where 25 grams of Na. Cl is dissolved in 250 m. L of water?

Dilutions � Most chemicals come from the chemical company in the most concentrated form. � For example, when we order hydrochloric acid it comes in a big stock bottle with a concentration of 15 M. � Most of the labs that we do only require 1. 0 M HCl. � How do we make a 1. 0 M solution?

Dilution Problems � A stock solution of 1. 00 M Na. Cl is available. How many milliliters are needed to make 100. 0 m. L of 0. 750 M Na. Cl? M 1 V 1 = M 2 V 2

Practice—How Many Grams of Cu. SO 4 5 H 2 O (MM 249. 69) are in 250. 0 m. L of a 1. 00 M Solution? Tro's Introductory Chemistry, Chapter 13 4

Practice—How Would You Prepare 100. 0 m. L of 0. 100 M K 2 SO 4 (MM = 174. 26)? Tro's Introductory Chemistry, Chapter 13 5

Molality (m) � m = moles solute / kilograms solvent What is the molality of a solution where 45 grams of Na. Cl is dissolved in 333 grams of solvent?

How Many Liters of 0. 115 M KI Is Needed to React with 0. 104 L of a 0. 225 M Pb(NO 3)2? 2 KI(aq) + Pb(NO 3)2(aq) 2 KNO 3(aq) + Pb. I 2(s) Tro's Introductory Chemistry, Chapter 13 7

How Many Liters of 0. 0623 M Ba(OH)2(aq) Are Needed to React with 0. 438 L of 0. 107 M HCl? Ba(OH)2(aq) + 2 HCl(aq) Ba. Cl 2(aq) + 2 H 2 O(l) Tro's Introductory Chemistry, Chapter 13 8

How many grams of iodine will react with 200 m. L of a 2 M solution of Na 2 S 2 O 3? Na 2 S 2 O 3 + I 2 Na. I + Na 2 S 4 O 6