1. 1. Write a balanced chemical equation for the reaction between solid zinc and solid sulfur. 2. What is the reaction type? Day 4 9-26

2. You do NOT have to write this one: Sit with your lab group from Friday and get out your lab handout! Day 5 9-29

3. Lab Reports are due Wednesday 10-1 Monday 9-29 for bonus

4. You do NOT have to write this one: Sit with your lab group from Friday and get out your lab handout! Day 6 9-30

6. Lab Reports are due Wednesday 10-1 Monday 9-29 for bonus

7. CORRECT AMOUNT = 3.21 grams 1/10 the molar mass of Zn reacts with 1/10 of the molar mass of S So why is it 1/10 for 1/10? Why not 1/10 for 2/10 or 3/10? And where’d the masses come from?

8. The key came from a combination of the atomic masses and the chemical equation: Zn + S  ZnS For every one “piece” of Zn we need one “piece” of S to form one “piece of ZnS 1/10 for 1/10

9. So where’d the masses come from?

10. So what was the key?

12. A mole is like a dozen, BUT better, How? A mole is a counter like a dozen, but it also relates to mass!!!

13. Avogadro’s # 6.022 * 10 23 = 1 mole The atomic mass = 1 mole Ca 20 Calcium 40.08

14. Avogadro’s # 6.022 * 10 23 = 1 mole Conversion Factors: 6.022 * 10 23 particles 1 mol 6.022 * 10 23 particles

15. Molar Mass – the mass of one mole of the substance is its molar mass (g/mol) = atomic mass of the element - The molar mass of an element contains 1 mole of atoms (6.022 * 10 23 atoms) So …

16. We can convert from grams to moles to atoms and back and forth and everything in between

17. We have a new kind of conversion: If you know grams of some to moles using the molar mass on the periodic table: substance you can convert 820 g of Iron (Fe) = __________ mols?

18. 820 g Fe X 55.847 g Fe 1 mol Fe = 1.5 * 10 1 mols Fe

19. 820 g of oxygen (O) = _________ mols? 820 g O X 15.999 g O 1 mol O = 5.1 * 10 1 mols O

20. If mols count atoms, What can we tell about the atoms of Fe compared to the atoms of O??? = Masses - More Oxygen atoms Therefore Iron atoms Must be bigger

21. 6.54 g of Zinc = __________ mols? 6.54 g Zn X 65.4 g Zn 1 mol Zn = 1.00 * 10 -1 mols Zn

22. Read + review section 10.1 (pages 306-315) AND complete #s 9-15  due on Thursday 10-2