1. Friday March 27 Objective: Determine the limiting reactant in a chemical reaction. Determine how much product can be made. Checkpoint: Given the equation: 2 H 2 + O 2  2 H 2 O If you have 0.50 grams of H 2, how many grams of H 2 O can you make if everything goes perfectly (your theoretical yield)? Not all of your oxygen reacted and you only made 2.15 grams of water. What is your percent yield? Homework: – Limiting Reactant notes & problems (due Monday) – Stoichiometry study guide (due Wed/Thurs), test on Friday

2. 0.50 g H 2 X g H 2 O mol H 2 O X X mol H 2 g H 2 2.02 1 1 18.02 2 2 4.46 g H 2 O (theoretical yield) mol H 2

3. Not all of your oxygen reacted and you only made 9.25 grams of water. What is your percent yield? actual yield % yield = ----------------------- x 100 theoretical yield 2.15 g H 2 O (actual yield) 4.46 g H 2 O (theoretical yield) 2.15 g ---------- x 100= 48.21 % yield 4.46 g

4. MgO Lab Report (1 day late) Pre-lab questions Data Table (with units) Calculations (show your work, box your answer) Conclusion: – Did you meet your goal of making exactly 0.50 grams of MgO? – Restate the value you got for % yield. – What are some sources of error in your experiment that prevented you from getting 100% yield and 0 % error?

5. Limiting Reactants Exercise Google Slides Presentation (1 presentation per group of 4) share with losaltos.science@gmail.com – Title Slide (with class name and group member names) – Slide that restates the problem. – Solution to the problem. – Pictures / Graphics with your procedure.

6. Limiting Reactants 2 H 2 + O 2  2 H 2 O If you have 10.0 grams of hydrogen and 15.0 grams of oxygen, how much water can you make? If you have 5 pieces of bread and 4 hamburger patties, how many hamburgers can you make?

8. Making a Gas Lab CH 3 COOH + NaHCO 3  CH 3 COOHNa + H 2 O + CO 2 If you are finished, you may work on the study guide due (Wed/Thurs)

9. CH 3 COOH + NaHCO 3  CH 3 COOHNa + H 2 O + CO 2 0.04 mol baking soda 0.08 mol baking soda 0.16 mol baking soda

10. CH 3 COOH + NaHCO 3  CH 3 COOHNa + H 2 O + CO 2 0.04 mol baking soda 0.08 mol baking soda 0.16 mol baking soda 0.08 mol vinegar

11. 1 hamburger 2 hamburgers

12. Limiting Reactant

16. 82p+83s+45b=how much left over? 41(2p+2s+1b=Bed) 82p+82s+41b=41 Beds

17. 2 H 2 + O 2  2 H 2 O What is your limiting and excess reactants if you have 5.43 grams of hydrogen and 17.03 grams of oxygen? 5.43 g H 2  g H 2 O 17.03 g O 2  g H 2 O 48.44 g H 2 O 19.18 g H 2 O Limiting reactant Excess reactant

18. 2 H 2 + O 2  2 H 2 O What is your limiting and excess reactants if you have 5.43 grams of hydrogen and 17.03 grams of oxygen? 5.43 g H 2  mol H 2 17.03 g O 2  mol O 2 2.69 mol H 2 0.53 mol O 2 O 2 = Limiting reactant H 2 = Excess reactant 5.43 g H 2 X mol H 2 g H 2 2.02 1 17.03 g O 2 X mol O 2 32.00 1 g O 2 / 2 / 1 1.34 0.53

19. Balance the reactions first!!!