1. Catalyst 1. How many dozens do you have if you have 120 pencils? 2. There are 10 millimeters in a centimeter. If I have 5 centimeters, how many millimeters do I have? 3. What is the molar mass of CaCO 3 ?

2. Today’s Agenda 5 min Catalyst 5 min Stoichiometry Big Picture 20 min Grams to Moles 15 min Practice 5 min Exit Slip

3. BIG GOAL!  Stoichiometry is a lot of little pieces  Important to keep big picture in mind  A question… How many bags of chips would you have to give up to buy a video game?

4. WHY? THIS GRAPHIC IS YOUR NEW BEST FRIEND! (so write it down) What can it tell you? 2H 2 + O 2  2H 2 O Moles Substance A Moles Substance B Grams Substance A Grams Substance B Molar Mass Mole Ratio Molar Mass

5. How? We can use dimensional analysis to convert between quantities of chemicals. Number and unit you were given Conversion Factor (unit you want) Conversion Factor (unit you were given)

6. Today’s Agenda 5 min Catalyst 5 min Stoichiometry Big Picture 20 min Grams to Moles 15 min Practice 5 min Exit Slip

7. Grams to Moles  Today, we will start off with the first part of the graphic. Going from grams of a substance, to moles of the same substance. We use the same steps for dimensional analysis that we did yesterday. Moles Substance A Moles Substance B Grams Substance A Grams Substance B Molar Mass

8. GRAMS TO MOLES Grams to Moles: 1. Find the molar mass of the compound Example: For H 2 O, 18 g/mol is the same thing as 18g = 1 mol. 2. Use the molar mass as a conversion factor

9. Grams to Moles Example  How many moles of CaCO 3 are there in 145 grams of CaCO 3  Step 1: What is the molar mass of CaCO 3 ?  Step 2: Use the molar mass as a conversion factor

10. Grams to Moles Example 2 How many moles of CCl 4 are there in 265 grams of CCl 4 ?

11. CHECK IN PRACTICE In your notes, try the next two problems silently and by yourself: 1. How many moles of CO 2 are there in 86 grams of CO 2 ? 2. How many moles of CaCl 2 are there in 100 grams of CaCl 2 ?

12. Moles to Grams Example 3 How many grams of NaCl are there in 6 moles of NaCl? (Backwards! But still find the molar mass.)

13. CHECK IN PRACTICE In your notes, try the next problem silently and by yourself: 1. How many grams of ZnO 2 are there in 5 moles of ZnO 2 ?

14. Today’s Agenda 5 min Catalyst 5 min Stoichiometry Big Picture 20 min Grams to Moles 15 min Practice 5 min Exit Slip

15. CHECK IN PRACTICE 1. How many grams of NO 3 are there in 4.2 moles of NO 3 ? 2. How many grams of LiBr are there in 3.7 moles of LiBr? 3. How many moles of LiBr are there in 112 grams of LiBr? 4. How many grams of BeF 2 are there in 4 moles of BeF 2 ? 5. How many moles of BeF 2 are there in 150 grams of BeF 2 ?

16. Today’s Agenda 5 min Catalyst 5 min Stoichiometry Big Picture 20 min Grams to Moles 15 min Practice 5 min Exit Slip

17. 1. What, in general, is the conversion factor when going from grams to moles? 2. How many moles of H 2 O are there in 100 grams of H 2 O?