1. Stoichiometry Introduction to Stoichiometry

2. Stoichiometry  Objectives  Define stoichiometry  Describe the importance of the mole ratio in stoichiometric calculations  Write a mole ratio relating two substances in a chemical equation

3. Stoichiometry  Stoichiometry Definitions  Composition stoichiometry deals with the mass relationships of elements in compounds  Reaction stoichiometry involves the mass relationships between reactants and products in a chemical reaction

4. Stoichiometry  Reaction Stoichiometry Problems  Problem Type 1: Given and unknown quantities are amounts in moles Amount of given substance (mol) Amount of unknown substance (mol)

5. Stoichiometry  Reaction Stoichiometry Problems  Problem Type 2: Given is an amount in moles and unknown is a mass Amount of given substance (mol) Amount of unknown substance (mol) Mass of unknown substance (g)

6. Stoichiometry  Reaction Stoichiometry Problems  Problem Type 3: Given is a mass and unknown is an amount in moles Mass of given substance (g) Amount of given substance (mol) Amount of unknown substance (mol)

7. Stoichiometry  Reaction Stoichiometry Problems  Problem Type 4: Given is a mass and unknown is a mass Mass of a given substance (g) Amount of given substance (mol) Amount of unknown substance (mol) Mass of unknown substance (g)

8. Stoichiometry  Mole Ratio  A mole ratio is a conversion factor that relates the amounts in moles of any two substances involved in a chemical reaction 2Al 2 O 3 (l) → 4Al(s) + 3O 2 (g) 2 mol Al 2 O 3 2 mol Al 2 O 3 4 mol Al 4 mol Al 3 mol O 2 3 mol O 2,,

9. Stoichiometry  Converting Between Amounts in Moles

10. Stoichiometry  Stoichiometry Calculations

11. Stoichiometry  Stoichiometry Calculations  Sample Problem  For each equation, balance and write all possible mole ratios HgO (s)Hg (l) + O 2 (g) NH 3 (g) + NO (g) N 2 (l) + H 2 O (l)

12. Stoichiometry  Stoichiometry Calculations  Sample Problem  How many moles of sodium will react with water to produce 4.0 mol of hydrogen in the following reaction? Na(s) + H 2 O(l)  NaOH(aq) + H 2 (g)

13. Stoichiometry  Stoichiometry Calculations  Sample Problem  How many moles of lithium chloride will be formed by the reaction of chlorine with 0.046 mol of lithium bromide in the following reaction? LiBr(aq) + Cl 2 (g)  LiCl(aq) + Br 2 (l)

14. Stoichiometry  Stoichiometry Calculations  Sample Problem  Aluminum will react with sulfuric acid in the following reaction. Al(s) + H 2 SO 4 (l)  Al 2 (SO 4 ) 3 (aq) + H 2 (g)  How many moles of H 2 SO 4 will react with 18 mol Al?  How many moles of each product will be produced from 18 mol Al?

15. Stoichiometry  Stoichiometry Calculations  Sample Problem  Propane burns in excess oxygen according to the following reaction. C 3 H 8 + O 2  CO 2 + H 2 O  How many moles each of CO 2 and H 2 O are formed from 3.85 mol of propane?  If 0.647 mol of oxygen is used in the burning of propane, how many moles each of CO 2 and H 2 O are produced? How many moles of C 3 H 8 are consumed?