1. Stoichiometry The quantitative study of chemical reactions

2. Stoichiometric Steps Set up & balance rxn Change stuff given to moles Change moles given to ask Change what’s asked for to the proper unit

3. Step 1 Determine products of a reaction if they are not given Balance the reaction

4. Step 2 Use molar conversion to change whatever is given to moles

5. Step 3 Use the molar ratio from the balanced reaction to convert the moles of what is given to the moles of what’s asked for.

6. Step 4 Use molar conversions to change the moles of what is asked for to the proper unit

7. Calculate the volume of NH 3 formed at STP when 6.0 kg of H 2 react with excess N 2 to form NH 3

8. Drill: Calculate the number of molecules of oxygen gas required to burn 3.0 ng of C 5 H 10 O 5

9. Chm II: Calculate the mass of Lead(II)iodide formed when 66.2 g of lead (II)nitrate is combined with excess potassium iodide

10. AP: Calculate the mass of solid product formed when 66.2 g of lead (II)nitrate is combined with excess potassium iodide solution

11. Chm II: Calculate the mass of MgCO 3 formed when 18.4 g of MgBr 2 is combined with a solution containing excess K 2 CO 3.

12. Homework Problem: 60 Page 78

13. AP: Calculate the mass of solid product formed when 18.4 g of MgBr 2 is combined with a solution containing excess K 2 CO 3.

14. Chm II: Calculate the volume at STP of CO 2 formed when 16.8 g of MgCO 3 is decomposed creating CO 2 & MgO.

15. AP: Calculate the volume at STP of gas formed when 16.8 g of MgCO 3 is decomposed by heat.

16. Limiting Reactant The reactant that gets used up The reactant that determines the amount of product formed

17. Excess Reactant The reactant that Does Not get used up

18. Stoichiometry with Multiple Reagents Perform same steps for all reactants Choose least amount of product

19. Calculate the mass of glucose (C 6 H 12 O 6 ) formed when 880 g of carbon dioxide is combined with 720 g of water in photosynthesis

20. Chm II: Calculate the mass of BaSO 4 formed when 104 g of BaCl 2 is combined with 250 mL 1.00 M K 2 SO 4

21. AP: Calculate the mass of solid formed when 104 g of BaCl 2 is combined with 250 mL 1.00 M K 2 SO 4

22. AP Drill: Calculate the mass of solid formed when 26.1 g of Ba(NO 3 ) 2 is combined with 25 mL 1.00 M K 2 SO 4

23. Theoretical Yield The amount determined through stoichiometry The amount solved for on paper

24. Experimental Yield The amount obtained in the lab Actual yield

25. Percent yield % Yield = (Exp/Theo) x 100 %

26. 68 g NH 3 was obtained in lab when 140 g of N 2 reacts with excess H 2. Calculate percent yield.

27. Drill: 510 g PH 3 was obtained when 0.62 kg of P 4 reacts with excess H 2. Calculate percent yield.

28. Review HW Problem 31 on page 115

29. Determine the mass of PH 3 formed at STP when 2.0 x 10 27 molecules P 4 reacts with 4.0 kg of H 2 :

30. Determine the volume of O 2 released at STP when 32 kg of Fe 2 O 3 is purified with an 80.0 % yield making Fe & O 2

31. Calculate the volume of oxygen gas at STP required to burn 12 kg of erythrose (C 4 H 8 O 4 )

32. Calculate the mass of solid product formed when 41.6 g of barium chloride is added to 250 ml of 0.40 M potassium sulfate giving a 50.0 % yield:

33. Calculate the mass of solid product formed when 2.00 g of calcium bromide is added to 250 ml of 0.40 M sodium sulfate:

34. 4.61 g of lead(II)iodide was obtained when 66.2 g of lead(II)nitrate was added to 750 ml 0.10 M potassium iodide. Calculate the % yield & the molarity of all ions remaining in the solution.

35. 33.1 g of lead(II)nitrate was added to 1500 mL 0.10 M potassium iodide. Calculate mass of solid product formed.

36. An 30.0 g unknown sample (containing only C, H, & O) was burned in excess oxygen yielding 66 g CO 2 & 36 g H 2 O. Calculate its empirical formula :

37. An 240 g unknown sample (containing only C, H, S, & O) was burned in excess oxygen yielding 352 g CO 2, 144 g H 2 O, & 128 g, SO 2. Calculate its empirical formula :

38. Calculate the volume of oxygen gas at STP required to burn 240 mg C 5 H 8 O 2 :