1. 1 Stoichiometry Mol Factors Calculations with Equations

2. 2 Mole-Mole Factor Shows the mole-to-mole ratio between two of the substances in a balanced equation Derived from the coefficients of any two substances in the equation

3. 3 Writing Mole Factors 4 Fe + 3 O 2 2 Fe 2 O 3 Fe and O 2 4 mol Feand3 mol O 2 3 mol O 2 4 mol Fe Fe and Fe 2 O 3 4 mol Feand2 mol Fe 2 O 3 2 mol Fe 2 O 3 4 mol Fe

4. 4 O 2 and Fe 2 O 3 3 mol O 2 and2 mol Fe 2 O 3 2 mol Fe 2 O 3 3 mol O 2

5. 5 Learning Check S1 3 H 2 (g) + N 2 (g) 2 NH 3 (g) A. A mol factor for H 2 and N 2 is 1) 3 mol N 2 2) 1 mol N 2 3) 1 mol N 2 1 mol H 2 3 mol H 2 2 mol H 2 B. A mol factor for NH 3 and H 2 is 1) 1 mol H 2 2) 2 mol NH 3 3) 3 mol N 2 2 mol NH 3 3 mol H 2 2 mol NH 3

6. 6 Solution S1 3 H 2 (g) + N 2 (g) 2 NH 3 (g) A. A mol factor for H 2 and N 2 is 2) 1 mol N 2 3 mol H 2 B. A mol factor for NH 3 and H 2 is 2) 2 mol NH 3 3 mol H 2

7. 7 Chemical Calculations 4 Fe + 3 O 2 2 Fe 2 O 3 How many moles of Fe 2 O 3 are produced when 6.0 moles O 2 react? 6.0 mol O 2 x mol Fe 2 O 3 = 4.0 mol Fe 2 O 3 mol O 2

8. 8 Learning Check 2 4 Fe + 3 O 2 2 Fe 2 O 3 How many moles of Fe are needed to react with 12.0 mol of O 2 ? 1) 3.00 mol Fe 2) 9.00 mol Fe 3) 16.0 mol Fe

9. 9 Solution S2 4 Fe + 3 O 2 2 Fe 2 O 3 12.0 mol O 2 x mol Fe = 16.0 mol Fe mol O 2 4 3

10. 10 Learning Check S3 4 Fe + 3 O 2 2 Fe 2 O 3 How many grams of O 2 are needed to produce 0.400 mol of Fe 2 O 3 ? 1) 38.4 g O 2 2) 19.2 g O 2 3) 1.90 g O 2

11. 11 Solution S 3 0.400 mol Fe 2 O 3 x 3 mol O 2 x 32.0 g O 2 2 mol Fe 2 O 3 1 mol O 2 = 19.2 g O 2

12. 12 Calculating Mass of A Substance Balance equation Convert starting amount to moles Use coefficients to write a mol-mol factor Convert moles of desired to grams

13. 13 Calculation The reaction between H 2 and O 2 produces 13.1 g of water. How many grams of O 2 reacted? Write the equation H 2 (g) + O 2 (g)H 2 O (g) Balance the equation 2 H 2 (g) + O 2 (g)2 H 2 O (g)

14. 14 Organize data mol bridge 2 H 2 (g) + O 2 (g)2 H 2 O (g) ? g 13.1 g Plan g H 2 O mol H 2 O mol O 2 O 2 Setup 13.1 g H 2 O x 1 mol H 2 O x 1 mol O 2 x 32.0 g O 2 8.0 g H 2 O2 mol H 2 O 1 mol O 2 = 11.6 g O 2

15. 15 Points to Remember 1. Read an equation in moles 2. Convert given amount to moles 3. Use mole factor to give desired moles 4. Convert moles to grams grams (givengrams (desired) moles (given)moles (desired)

16. 16 Learning Check S 4 How many O 2 molecules will react with 505 grams of Na to form Na 2 O? 4 Na + O 2 2 Na 2 O Complete the set up: 505 g Na x 1 mol Na x ________ x _______ 23.0 g Na

17. 17 Solution S 4 4 Na + O 2 2 Na 2 O 505 g Na x 1 mol Na x 1 mol O 2 x 6.02 x 10 23 23.0 g Na 4 mol Na 1 mol O 2 = 3.30 x 10 24 molelcules

18. 18 Learning Check S5 Acetylene gas C 2 H 2 burns in the oxyactylene torch for welding. How many grams of C 2 H 2 are burned if the reaction produces 75.0 g of CO 2? 2 C 2 H 2 + 5 O 2 4 CO 2 + 2 H 2 O 75.0 g CO 2 x _______ x _______ x _______

19. 19 Solution S5 2 C 2 H 2 + 5 O 2 4 CO 2 + 2 H 2 O 75.0 g CO 2 x 1 mol CO 2 x 2 mol C 2 H 2 x 26.0 g C 2 H 2 44.0 g CO 2 4 mol CO 2 1 mol C 2 H 2 = 22.2 g C 2 H 2

20. 20 Pathways for Problems Using Equations Given (A) Find (B) grams (A)grams (B) moles (A) moles (B) particles (A)particles (B)

21. 21 Pathways for Problems Using Equations Given (A) Find (B) grams (A)grams (B) molar molar mass (A) mass (B) coefficients moles (A) moles (B) Avogadro's Avogradro’s number number particles (A)particles (B)