Warm Up #1 You are given powdered lemonade mix. How do you make lemonade? [use the word ‘dissolve’ in your answer]

Chapter 7 Solutions

You’ve Heard the Word “Solution” used…what the hell does it mean? Solution – an evenly mixed homogeneous mixture Solute – the thing being dissolved (powder) Solvent – the thing doing the dissolving (water)

Aqueous Solutions and Concentration Aqueous (aq) – A solution where WATER is the solvent Water = universal solvent (can dissolve almost ANYTHING) Concentration – how much solute is in a solution

Types of Solutions Unsaturated – Solute still can dissolve in the solution (liquid) LOW CONCENTRATION Saturated – no more solute can dissolve in the solution (solid) HIGH CONCENTRATION

Quick Quiz #1 1. What is an aqueous solution. What is the symbol? 2. How do unsaturated and saturated solutions differ? Use the word “concentration” in your answer. 3. What is a solute? What is a solvent? Which one of those two does water usually act like?

Warm Up #2 You put Kool-Aid powder into water to make Kool-Aid. 1. What is the solute? 2. What is the solvent? 3. Say you drink what you have made and it is too strong (you put in too much powder). What do you do to make it less strong?

Concentrations with Math Molarity (M) – another word for concentration How much solute is in a given volume (size) solution MUSCLE MILK: CONCENTRATED PROTEIN!

Conversions Review: For your T-Charts VOLUME: 1 L = 1000 mL = 1000 cm 3 GRAMS TO MOLES : PERIODIC TABLE ATOMS TO MOLES : 6.02x10 23

Quick Quiz #2 1. There are 5 moles of HCl in a 30L solution. What is the molarity? 2. Mr. Lockett put 80 grams of Calcium into a 10L solution. What is the molarity? 3. Jessica placed 5 moles of Copper into a solution of 3000 milliliters. What is the molarity?

Warm Up #3 Mary placed Kool-Aid powder in water… 1. Is the solution aqueous or not? How do you know? 2. If she had 5 mol of Kool-Aid in a 250mL solution, what is her concentration (convert mL to L first). 3. If she stirred the solution, do you think the dissolving process would be sped up, or slowed down? Why do you think so?

Dilutions

Dilute vs. Concentrated Concentrated – a LOT of solute being dissolved Dilute – small amount of solute being dissolved OR Adding MORE solvent to make solution LESS concentrated

Dilution Equation Equation: M 1 V 1 = M 2 V 2 M 1 = INITIAL concentration (mol/liter) V 1 = INITIAL volume (liters) M 2 = FINAL concentration (mol/liter) V 2 = FINAL volume (liters)

Example Problem Ricardo had a solution of an unknown concentration, in a 40mL container. When he moved it to a 60mL container, he found the concentration was.450 M. What was the original concentration? M 1 = V 1 = M 2 = V 2 =

Quick Quiz #2 1. M 1 =.15 MV 1 = ??? M 2 =.367 M V 2 = 1.4 L 2. Olga wanted to know how much solution (in milliliters) she started with, if she originally had a 4.5 M solution, and then placed it in a 500 mL container that changed it to a 2.3 M solution.

M 1 V 1 = M 2 V 2 Dissolving Rate Dissolving – when solute is broken down by solvent DUE TO: RANDOM particle motion Things Affecting Rate: Temperature – higher temp = faster dissolving Stirring – more stirring = faster dissolving Surface Area– more surface area = faster dissolving

Warm Up #4 1. Use the Periodic table to find the masses of the following : SCO 2 H 2 SO 4 2. How many particles (atoms) are in 6 mols of Carbon? (1 mol = 6.02x10 23 atoms)

Equilibrium and Reaction Rates

Warm Up #5 CH O 2 ⇌ CO H 2 0 What is the mole to mole ratio of CH 4 and CO 2 ? If 32 grams of CH 4 react with O 2, how many moles of CO 2 will form? How many grams of CO 2 ?

Grams to Grams

What is an Equilibrium? Equilibrium – there is balance between the reactants and products in a chemical reaction. There is no change in the chemical reaction. Reactants – starting materials Products – ending materials In a Chemical Reaction: ⇌ used instead of 

Equilibrium – Two Kinds Homogeneous Equilibrium – All substances are in the SAME state of matter (solid, liquid or gas). HOMO- = same Example: CaCO 3 (s) ⇌ CaO(s) + CO 2 (s) Heterogeneous Equilibrium – Substances are in DIFFERENT states of matter (solid, liquid or gas). HETERO - = different Example: 2 N 2 (g) + O 2 (g) ⇌ 2 N 2 0 (l)

2 N 2 (g) + O 2 (g) ⇌ 2 N 2 0 (l) Mole to Mole Ratio – the amount of moles of one thing compared to the other. __ to __ ratio Number in front of Compound (if none, 1) Ex. Moles of N 2 and Moles of O 2 = 2 to 1 Ratio

Grams A to Grams B Flow Chart Grams A Moles AMoles B Grams B

Grams A to Grams B T-Chart Grams A Moles A Moles B Grams B Given Periodic Table Mole to Mole Ratio Periodic Table

Example: NaOH + HCl  H NaCl A = NaOHB = NaCl Ex. 1: Convert MOLES of NaOH into MOLES of NaCl You start with 2.6 mol of NaOH Ex. 2: Convert GRAMS of NaOH into MOLES of NaCl You start with 98 grams of NaOH Ex. 3: Convert GRAMS of NaOH into GRAMS of NaCl You start with 98 grams of NaOH

Quick Quiz 2 AgI + FeO  Ag 2 O + FeI 2 A = AgIB = FeI 2 What is the mole to mole ratio of AgI and FeI 2 ? (__ to __ ratio) You start with 300 GRAMS of AgI, convert into GRAMS of FeI 2

Review Equilibrium = balance between reactants (starting materials) and products (ending materials) Symbol: ⇌ What happens when this balance is upset? How does it reset itself?

LeChatlier’s Principle LeChatlier’s Principle - If equilibrium is upset, how the reaction resets itself to be in equilibrium: How the equilibrium can be affected: Changes in Pressure Changes in Temperature Changes in Concentration

Reaction: N H 2 ⇌ 2 NH 3 This solution is at equilibrium BUT: CHANGE CONC. Add more N 2  shift to the RIGHT to balance Less N 2  shift to the LEFT to balance

Grab a lab sheet and a piece of paper: Copy Down: Name/Period/Date Title Purpose Materials (cross out “tap water” and write “hand sanitizer” instead!)

Warm Up #1 A + B  C + D If this reaction was ENDOTHERMIC, which two things would HEAT go with? If this reaction was EXOTHERMIC, which two things would HEAT go with?