1. Stoichiometry Warm-Up Question(s)

2. Warm-up How many seconds are there in 72 hours? Show your work.

3. Overview Stoichiometry is used to make sense of a chemical equation….Quantitatively. Why use the mole? –It is impossible to weigh out an individual molecule or molecules. –We use the molar mass to help with this.

4. p. 334 Solved Problem You must use a mole (molar) ratio of the reactants to solve for moles of a product. –Ex:2 Al (s) + 3Cl 2 -> 2AlCl 3 (s) –3 moles of Cl 2 = 2 moles of AlCl 3

5. Solved Problem p. 337 You must use a molar mass of a compound to solve for moles of that compound. Ex: 1 mole of CaCO 3 = 40.08g + 12.01g + (16.0g x 3) = 100.09 g Molar mass of CaCO 3 = 100.09 g/mole Use the molar mass as a conversion factor.

6. Solved Prob p. 338 Work on Own Ques. 362 - 363 #39, 41, 43

7. Example Problem A sample of potassium chlorate is heated and decomposes according to the following equation: 2 KClO 3 → 2 KCl + 3 O 2 If 11.2 grams of potassium chlorate decompose completely, how many grams of potassium chloride will be produced from this reaction?