Warm Up 5.6: Mg + 2HCl  MgCl 2 + H 2 What volume of hydrogen gas at STP will be produced from each reactant when 50g of magnesium reacts with 75g of hydrochloric acid? ( Hint: 2 separate problems/grids) 50 g Mg 75g HCl

Warm Up 5.6: Mg + 2HCl  MgCl 2 + H 2 What volume of hydrogen gas at STP will be produced from each reactant when 50g of magnesium reacts with 75g of hydrochloric acid? ( Hint: 2 separate problems/grids) 50 g Mg 75g HCl

1 number in the problem = 1 stoich 2 numbers in the problem = 2 stoich

A stool is: 1 top 3 legs How many stools can be made with four tops and twenty-three legs? Draw Combinations : Draw Extras: How many stools were made? How many extras were there?

Conclusion: 1. What determined how many stools were made? the tops of stool 2.What was the extra? legs 3. Limiting Reactant is: determines how much is made; used up completely; forms the smallest amount 4 Excess Reactant is: extra; not completely used up in rxn; produces the biggest amount

 You have 18 car bodies and 43 tires. How many cars could you build? What is the limiting and excess reactant?  You have 23 pieces of bread, 18 pieces of ham, and 29 pieces of cheese. How many ham and cheese sandwiches could you make? What is the limiting and excess reactant?

 You need 20 mL of chocolate syrup and 250 mL of milk to make one glass of chocolate milk. If you have 433mL of chocolate syrup and 2987 mL of milk, how many glasses of chocolate milk can you make? What is the limiting and excess reactant?

Ex. 1 2Na(s) + Cl 2 (g)  2NaCl(s) 1) A = 6.70 mol Na 2) A = 3.2 mol Cl 2 A =? mol NaCl A =? mol NaCl

Ex. 1 2Na(s) + Cl 2 (g)  2NaCl(s) 1) A = 6.70 mol Na 2) A = 3.2 mol Cl 2 A =? mol NaCl A =? mol NaCl

 Which number is smaller?  Which reactant limits the amount of product produced?  What is the max amount of product produced?  You want to make cherry-grape koolaid, you have 1 packet of cherry and 2 packets of grape, how many pitchers of cherry- grape koolaid can be made?

 Which number is smaller? 6.4 mole NaCl  Which reactant limits the amount of product produced? chlorine  What is the max amount of product produced? 6.4 mole NaCl  You want to make cherry-grape koolaid, you have 1 packet of cherry and 2 packets of grape, how many pitchers of cherry- grape koolaid can be made? 1 pitcher of cherry-grape

Definitions: Limiting Reactant/Reagent: Limits/determines the amt of product; completely used up in rxn – smaller # formed Excess Reactant/Reagent: not completely used up in rxn – BIGGER # formed; extra

Ex. 2 C 2 H 4 (g) + 3O 2 (g)  2CO 2 (g) + 2H 2 O If 2.7 mol of C 2 H 4 is reacted with 6.3 mol of O 2, what is the max amount of water in moles that can be produced? Identify the limiting and excess reactants.

Ex. 3 2Cu (s) + S (s)  Cu 2 S (s) If eighty grams of copper is reacted with twenty-five grams of sulfur, how much product can be produced in grams? Identify the limiting and excess reactants.

Ex. 3 2Cu (s) + S (s)  Cu 2 S (s) If eighty grams of copper is reacted with twenty-five grams of sulfur, how much product can be produced in grams? Identify the limiting and excess reactants.

Definitions: Theoretical Yield: MAX amt of product that can be produced  paper-pencil Actual Yield: amt of product that actually produced  done in lab

Percent Yield: % Yield = (Actual Yield/ Theoretical Yield )  100%

Ex. 4 CaCO 3 (s)  CaO (s) + CO 2 (g) What is the theoretical yield of calcium oxide if 24.8 grams of calcium carbonate is heated? What is the percent yield if 13.1 g calcium oxide is produced in lab?