1. Grab binders, handouts, returned work & calculators, begin the Do Now 5/16 DO NOW 1. Determine how many moles of H 2 O you would have if you were given 16g of H 2 O. 2. Determine how many grams of NaBr you would have if you were given 3 moles of NaBr. 3. Balance the following reaction: ___Cu + ___H 2 SO 4  ___Cu 2 SO 4 + ___H 2

2. Mandatory Office Hours by MON 5/20 P1 Josh A David A Nicholas Ruben Juan Kisha Antwan Dajon Lee Ciera P3 Darrion Maria William Delante Karina Bradley Jacques Leandrea Monica G4 Doneika Khari Perla La’Nesha Arturo Milton G5 Adalynn Arkita Tiana Angel Joey Raven Bob Deyja

3. Stoichiometry Part I Recap Molar Mass = sum of mass #’s of all elements in a compound (g/mol) Moles  Mass = moles x Molar Mass Mass  Moles = grams ÷ Molar Mass

5. Stoichiometry Part II Notes Key Point #1: To convert between moles X & moles Y = MULTIPLY Moles reactant by MOLAR RATIO Molar Ratio = coefficients of balanced reaction

6. Moles  Moles Example 1: 2H 2 O 2 (aq)  2H 2 O(l) + O 2 (g) 1.What is the molar ratio between H 2 O 2 and O 2 ? 2.If you start with 4 moles of H 2 O 2, how many moles of O 2 will you produce? 3. If you start with 8 moles of H 2 O 2, how many moles of H 2 O will you produce?

7. Moles  Moles Example 2: 2H 2 + O 2  2H 2 O 1.What is the H 2 / H 2 O mole ratio? 1.If you had 30 moles of H 2, how many moles of H 2 O could you make? 2.If you had 3 moles of H 2 O, how many moles of O 2 reacted?

8. Moles  Moles Example 3: N 2 (g) + 2CO 2 (g)  2CN(g) + 2O 2 (g) 1.What is the mole ratio between CO 2 and O 2 ? 1.If you start with 3 moles of CO 2, how many moles of O 2 will you produce? 3. If you start with 5 moles of N 2, how many moles of CN will you produce?

9. Stoichiometry Part II Notes Key Point #2: Steps to Climb the Mole Hill 1.Calculate the Molar Masses for the given and unknown 2.Convert given mass to moles 3.Convert moles of given to moles of unknown 4.Convert moles of unknown to mass of unknown

10. Climbing the Mole Hill Example 1: 2H 2 O 2 (aq)  2H 2 O(l) + O 2 (g) 1.If you start with 6 grams of H 2 O 2, how many grams of O 2 will you produce?

11. Climbing the Mole Hill Example 2: 2H 2 O 2 (aq)  2H 2 O(l) + O 2 (g) 2. If you produce 36 grams of H 2 O, how many grams of H 2 O 2 did you start with?

12. Climbing the Mole Hill Example 3: 2NaCl(aq) + Pb(NO 3 ) 2 (aq)  2NaNO 3 (aq) + PbCl 2 (s) 3. If you produce 30g of PbCl 2, how many grams of NaCl did you use?

13. Stoichiometry Debrief Conversion Factors: Molar Mass Molar Ratio Keep track of your UNITS & COMPOUNDS!

14. Lab 2: Biodegradable Soap Question:  determining this using pH Are natural, homemade soaps better or worse for our skin compared to generically mass-produced soaps?

15. Lab 2: Biodegradable Soap Data pH Scale: Soap BrandpH Lever9 Irish Spring9.5 Dove7 Homemade

16. Lab 2, Part 2 Directions: 1. Collect your lab group’s soap samples 2. Weigh the mass of ALL of your soap samples on an electronic balance. Record the total mass in your lab 2 data section! 3. Tear a small piece of soap from one of your samples and place into a clean test tube. 4. Fill the test tube ¾ of the way with water 5. Place your thumb over the open end of the test tube and shake vigorously to dissolve the soap 6. Dip one end of the pH strip into the soap solution. Allow the pH strip to dry completely (blow on it to help dry) 7. Use the pH scale located in the hood to assess your soap’s pH level. Record the pH of your soap in you lab 2 data section!

17. Lab 2: Biodegradable Soap Clean Up: -Empty soap solution down the sink -Throw out used pH strips -Collect your lab group’s soaps in a Zip Lock Bag from Ms. Herndon at the front desk. -Begin Post-lab Questions & Conclusion

18. Exit Ticket 6 Directions: You have 10 minutes to complete the Exit Ticket to the best of your ability. You MAY NOT use notes, but you may use a Periodic Table. When finished submit to the class bucket.