1. STOICHIOMETRY (Using balanced chemical equations to solve mole problems)

2. What do I know about stoichio metry? What do I want to know about stoichio metry? What did I learn today about stoichio metry?

3. T YPES OF PROBLEMS 1. Mass—mass (grams to grams) 2. Mass—volume (grams to liters OR liters to grams) 3. Volume—volume (liters to liters)

4. W HAT DO COEFFICIENTS TELL US IN A BALANCED EQUATION ? 1. Mole ratio *** 2. Molecule ratio 3. Liter ratio (only works for gases) **** EXAMPLE: 2 H 2 + __O2 ------ 2 H 2 O 2: 1: 2

5. 1 MOLE OF A SUBSTANCE EQUALS : 1. Avogadro’s number of particles 2. Molar mass (g/mole) *** 3. 22.4 L of a gas (AKA molar volume) at STP(standard temp & pressure) ***

6. V IDEO LINK www.khanacademy.org (Stoichiometry)

7. M ASS ----M ASS PROBLEMS 1. Balance the equation. 2. Underneath the equation, write what’s “given” and what’s “wanted”. 3. Convert grams to moles (using molar mass). 4. Convert moles of “given” to moles of “wanted” (using coefficient ratio). 5. Convert moles to grams (using molar mass). 6. The “given” determines sig figs for your answer.

8. Given’s mass X 1 mole X unknown’s coeff X molar mass of unknown molar given’s coefff1 mole mass of given

9. E XAMPLE How many grams of sodium oxide are formed when sodium reacts with 42 grams of oxygen? 4 Na + ___O 2 ------- 2 Na 2 O 42 g ?g 42 g O 2 x 1 mole x 2moles Na 2 O x 62 g 32 g1 mole O 2 1 mole 42 x 2 x 62 =162.75 = 160 grams 32 x 1 x 1

10. How many grams of oxygen are required to produce 20.0 grams of water? 2 H2 + O2 -------- 2 H2O ?g 20.0 grams 20.0 g H2O x 1 mole x 1 mole O2 x 32 g O2 18 g 2 moles H2O 1 mole 20.0 x 32 18 x 2 =17.77 = 17.8 grams

11. ACTIVATOR WHAT ARE THE 3 TYPES OF STOICHIOMETRY PROBLEMS THAT WE WILL WORK?

12. P RACTICE PROBLEMS 1. How many grams of zinc chloride are produced when 50.0 grams of zinc metal react with hydrochloric acid? Zn + HCl ---------ZnCl 2 + H 2 ANSWER: 104 grams 2. If calcium oxide is prepared by heating calcium carbonate, how much calcium carbonate is required to produce 15.0 grams of calcium oxide? CaCO 3 --------CaO + CO 2 ANSWER: 26.8 grams

13. www.khanacademy.org (stoichiometry problem #1 and 2)

14. 2 TYPES OF REACTANTS LIMITING Is completely used up in the reaction Produces the least amount of product EXCESS Is still left over after the reaction occurs

15. A CTIVATOR : Write the balanced equation for the reaction which we will be doing in LAB today.