Grab binders, handouts, returned work & calculators, begin the Do Now 5/14 DO NOW 1. Balance the following reaction: ___AgNO 3 + ___K 2 S  ___Ag 2 S + ___KNO 3 2. Calculate the Molar Masses of the following compounds: H 2 SO 4, CaCO 3, Mg(OH) 2 3. If you wanted to buy cupcakes and each cupcake costs $2.50, how much money would you need in order to buy 10 cupcakes?

Stoichiometry -What is the mole? -What are the units for molar mass? -What are the units for mass? … all we are doing is converting between units

Stoichiometry Part I Notes Key Point #1: Converting between mass and moles is necessary… - to determine the proportions needed in a reaction - to predict how much of a new substance we can create - to regulate costs and not waste money

Stoichiometry art I Notes Key Point #2: In converting between moles and mass, you need MOLAR MASS To go from moles  mass = MULTIPLY moles x MOLAR MASS

Moles  Mass Steps to convert from moles to mass: Given – what is your given value and its units? Unknown – what are you solving for? Equation – set up the equation Solve for your unknown Sort your units…do they match up correctly?

Moles  Mass Let’s Practice: 1.How many grams are in one mole of Carbon? 2. How many grams are in 5 moles of KCl 3. How many grams are in 2 moles of Cu(OH) 2 ? 4. How many grams are in 8 moles of Au 2 SO 4 ? 5. How many grams are in 3 moles of H 2 SO 4 ?

Stoichiometry Part I Notes Key Point #2 continued … To go from mass  moles = DIVIDE mass by MOLAR Mass

Mass  Moles Let’s Practice: 1.How many moles is 12g of Carbon? 2. How many moles is 25g of KCl? 3. How many moles is 124g of Cu(OH) 2 ? 4. How many moles is 88g of Au 2 SO 4 ? 5. How many moles is 6g of H 2 SO 4 ?

Lab 3: Synthesizing Aspirin Question: Are brand name commercial prescription drugs better than generic or homemade prescription drugs? Directions: - Complete & submit Lab 2 (Introduction, Pre-Lab, & Hypothesis) - Draft Lab 3 Introduction, Pre-Lab Questions, & Hypothesis

Theoretical Yield C 7 H 6 O 3 (s) + C 4 H 6 O 3 (aq)  C 9 H 8 O 4 (s) + C 2 H 4 O 2 (aq) How much did we start with? Molar Masses? Mole Ratio? Lets climb up & down the mole hill…

Percent Yield & Percent Error Percent Yield: How much product you obtained Percent yield = (actual yield ÷ theoretical yield) x 100% Percent Error: How accurate you were Percent error = | actual yield – theoretical yield | x 100 % theoretical yield

Exit Ticket 5 Directions: You have 10 minutes to complete the Exit Ticket to the best of your ability. You MAY NOT use notes, but you may use a Periodic Table. When finished submit to the class bucket.

Stoichiometry Part II Notes Key Point #1: To convert between moles reactant & moles product = MULTIPLY Moles reactant by MOLAR RATIO Molar Ratio = coefficients of balanced reaction

Moles  Moles Let’s Practice: 2H 2 O 2 (aq)  2H 2 O(l) + O 2 (g) 1.What is the molar ratio between H 2 O 2 and O 2 ? 2.If you start with 4 moles of H 2 O 2, how many moles of O 2 will you produce? 3. If you start with 8 moles of H 2 O 2, how many moles of H 2 O will you produce?

Climbing the Mole Hill Let’s Put it all together: 2H 2 O 2 (aq)  2H 2 O(l) + O 2 (g) 1.If you start with 6 grams of H 2 O 2, how many grams of O 2 will you produce? 2.If you produce 36 grams of H 2 O, how many grams of H 2 O 2 did you start with?

Stoichiometry Debrief Conversion Factors: Molar Mass Molar Ratio Keep track of your UNITS!! GUESS