1. Chemical Equations Reaction Stoichiometry-the quantitative relationship among substances as they participate in a chemical reaction. 2Al(s)+ 3Br2(g) Al2Br6(s) Reactants Products 2Al, 6Br 2Al, 6Br s=solid g=gas l=liquid aq=aqueous

2. 2Hg2O(s)4Hg(l) + O2(g) 417.2g 200.6g+32.0g=232.6g 834.4g 802.4g+32.0g=834.4g Check 4Hg,2O 4Hg,2O = Heat

3. Balance the given chemical Rxn • NH3+O2NO+H2O1N,3H,2O 1N,2H,2O • 2NH3+O2NO+3H2O 2N,6H,2O 1N,6H,4O • 2NH3+O2NO+3H2O 2N,6H,2O 2N,6H,5O • 2NH3+5/2O2NO+3H2O 2N,6H,5O 2N,6H,5O • 4NH3+5O2NO+6H2O 4N,12H,10O 4N,12H,10O

4. 2Mg(s)+2HCl(aq) 2MgCl(aq) + H2(g) 2Mg, 2H, 2Cl 2Mg, 2H, 2Cl

5. 2Mg(s)+2HCl(aq) 2MgCl(aq) + H2(g) How many moles of HCl will react with 2.3 moles of Mg(s)? 2 moles HCl(aq) 2 moles Mg(s) 2.3 moles Mg * = 2.3 moles HCl How many moles of H2(g) will be produced if we react 22.3 g of Mg(s) with excess aqueous HCl? 1 mol Mg(s)1 mol H2(g) 24.3 g 2 mol Mg(s) 22.3 g Mg(s) * * = 0.459 mol H2 How many grams of H2(g)? 2.02 g 1 mol H2 0.4588 mol H2 * = 0.927 g H2

6. How many sandwiches can you make with 6 pieces of bread and 4 pieces of cheese? 2 pieces of bread/sandwich 1 piece of cheese/sandwich 6 pieces of bread * 1 sandwich/2pieces of bread = 3 sandwiches 4 pieces of cheese*1 sandwich/1piece of cheese = 4 sandwiches Therefore, the bread is the limiting factor.

7. Limiting Reactant Concept What is the maximum mass of sulfur dioxide that can be produced by the reaction of 95.6 g of carbon disulfide with 110 g of oxygen? Therefore, the limiting reagent is the Oxygen

9. Percent Yields from Reactions Theoretical Yield- what we have been calculating. Actual Yield - what you have in your flask