Unit 13 Solution Chemistry

What is a solution? A solution is a homogeneous mixture of two or more substances in a single phase. Requirements: 1. contains two or more substances 2. each substance maintains its own chemical identity 3. the substances combine in a single phase

Circle the solutions: GatoradeChocolate MilkIce CreamPeanut Butter Nail PolishDistilled waterVinegarHCl (aq) JelloShaving CreamApple juiceSalad dressing Salt waterocean waterpond waterdrinking water H 2 O(l)CuSO 4 (aq)SodaNaCl(s)

Solutions: GatoradeChocolate MilkIce CreamPeanut Butter Nail PolishDistilled waterVinegarHCl (aq) JelloShaving CreamApple juiceSalad dressing Salt waterocean waterpond waterdrinking water H 2 O(l)CuSO 4 (aq)SodaNaCl(s)

Parts of a solution: A solution is made up of two parts, the solute and the solvent. Solute = the substance being dissolved in a solutions, usually present in a smaller amount. Solvent = the substance used to dissolve the solute, usually present in a larger amount.

Parts of a solution: Which is present in the greater amount, the solute or solvent?

Concentration of a Solution: Qualitative (Non-quantitative) description of solution concentration: Concentrated = a solution that contains a lot of solute. Dilute = a solution that contains a small amount of solute. Some descriptions of solution concentration: 1.The solution is darker or lighter in color. 2.The solution is thick, not easy to pour.

Concentration of Solutions: Quantitative (measured) description of solution concentration: Molarity (M) = moles solute Liter solution Dilution: M 1 V 1 = M 2 V 2

Summary solution concentration word bank: concentrated, molarity, dilute ___________________ solutions have a high solute: solvent ratio. ____________________ solutions have a low solute: solvent ration ____________________ gives a quantitative measurement of solution concentration

Molarity calculations: 1.Write the equation for molarity: 1.What is the molarity of a solution containing 0.5 moles HCl in 1L solution? 2.Sea water contains roughly 28.0 g of NaCl per liter. What is the molarity of sodium chloride in sea water? 3. What is the molarity of 5.00g NaOH in 1.00 L solution? 4.How many moles of sodium carbonate (Na 2 CO 3 ) are there in 1.5L of a 2.0M solution?

Dilutions: M 1 V 1 = M 2 V mL of a 5.0M solution is diluted to 250 mL. Calculate the concentration (M 2 ) M1=M1= V 1 = M 2 = V 2 = 2. What volume (V 1 ) is needed to prepare 500. mL of a 1.0M NaCl solutions. The starting solution has a concentration of 2.5M. 3. Calculation the concentration (M2) of a solution prepared by diluting 25 mL of a 1.25M solution to a new volume of 150 mL.

Solubility and solutions: “likes dissolve likes” Solubility = the amount of solute that can dissolve in given amount of solvent (generally water, 100g) Unsaturated solution = less than the maximum amount of solute Saturated solution = the maximum amount of solute for a given amount of solvent Supersaturated solution = more than the maximum amount of solute is dissolved for a given amount of solvent

Solubility curve: Describes the relationship of solubility and temperature (  Temp =  Solubility) Think Ice tea and hot tea! 

Solubility Curve:

Solutions & Colligative Properties: Colligative properties are properties of solutions that depend upon the ratio of the number of solute particles to the number of solvent molecules in a solution. Properties that are affected include: Freezing point Boiling point Vapor pressure 1. The freezing point of a solvent is lowered when a solute is added to a solvent. 2. The boiling point of a solvent is raised when a solute is added to a solvent. 3. The vapor pressure of a solvent is lowered when a solute is added to a solvent.

Colligative properties: Applications: Salting icy roads and walkways Making ice cream or freezer pops in the lab!