1. The Mole Unit 5

2. Formula Mass Formula mass - also called: formula massmolecular mass molecular massformula weight formula weightmolecular weight molecular weightmolar mass molar weight the mass of one mole of a compound, atom or ion. (units: _g_ ) mol

3. Formula Mass: Example: Calculate the formula mass of the following: I Do: carbon tetrachloride Formula: CCl 4 1 C: 12.011 g/mol 4 Cl: 4 x 35.45 g/mol = 141.8 g/mol Total mass: 153.81 g/mol

4. Formula Mass Example: Find the formula mass of each of the following: We Do: arsenic trichloride: Formula: AsCl 3 1 As: 74.922 g/mol 3 Cl: 3 x 35.45 g/mol = 106.35 g/mol Total mass: 181.27 g/mol

5. Formula Mass Example: Find the formula mass of each of the following: You Do: potassium sulfide Formula: K 2 S 2 K: 2 x 39.098 g/mol = 78.196 g/mol 1 S: 32.066 g/mol Total mass: 110.262 g/mol

6. Measuring Matter There are three ways to measure matter: 1.By counting representative particles: atoms – element molecules- covalent compound formula units- ionic compound ions – anything with a charge. Al, Na, S, etc PCl 3,O 2, CO 2 AlCl 3,K 2 O, Ba 3 P 2 PO 3 2-,K 1+

7. 2. By mass - in grams 3. By volume - in liters for gases (at STP)

8. Measuring Matter 1 mole of a compound = formula mass (in grams) 1 mole of a compound = 6.02 x 10 23 representative particles 1 mole of a gas (STP) = 22.4 liters The mole is the link between grams, the number of representative particles and liters! Remember: There are 4 different types of Representative Particles Atoms Formula units Molecules Ions

9. Identify the type of Representative Particle NaCl F 2 NH 4 +1 CS 2 H 2 O Be CsF Formula Units Molecules Ions Molecules Atoms Formula Units

10. Mole Road Map

11. Mole Practice: One Step Conversions: Remember to show all work using dimensional analysis. I Do: How many moles are present in a tank of gas that contains 55.60 Liters? Conversion Factors: 1 mole = formula mass  1 mole or g g 1 mole 1 mole = 6.022 x 10 23  1 mole or 6.022 x 10 23 particles 6.022 x 10 23 1 mole 1 mole = 22.4 Liters gas  1 mole or 22.4 L 22.4 L 1 mole 55.60 Liters = 2.48 moles of gas Make sure to round the final Answer to the 100 th place. Only the final answer!

12. Mole Practice: One Step Conversions: Remember to show all work using dimensional analysis. We Do: How many moles are in 18.0 grams of sugar (C 6 H 12 O 6 )? Conversion Factors: 1 mole = formula mass  1 mole or g g 1 mole 1 mole = 6.022 x 10 23  1 mole or 6.022 x 10 23 particles 6.022 x 10 23 1 mole 1 mole = 22.4 Liters gas  1 mole or 22.4 L 22.4 L 1 mole 18.0 g C 6 H 12 O 6 Make sure to round the final Answer to the 100 th place. Only the final answer! Add Masses of 6C + 12H + 6O You must use all the Numbers from the Periodic Table

13. Mole Practice: One Step Conversions: Remember to show all work using dimensional analysis. You Do: What is the mass in grams of 4.50 moles of barium sulfide? Conversion Factors: 1 mole = formula mass  1 mole or g g 1 mole 1 mole = 6.022 x 10 23  1 mole or 6.022 x 10 23 particles 6.022 x 10 23 1 mole 1 mole = 22.4 Liters gas  1 mole or 22.4 L 22.4 L 1 mole 4.50 mol BaS Make sure to round the final Answer to the 100 th place. Only the final answer! Add Masses of 1 Ba + 1 S You must use all the Numbers from the Periodic Table

14. Two and Three Step Conversions I Do: What is the mass in grams of 5.02 x 10 24 formula units of potassium phosphate? Conversion Factors: 1 mole = formula mass  1 mole or g g 1 mole 1 mole = 6.022 x 10 23  1 mole or 6.022 x 10 23 particles 6.022 x 10 23 1 mole 1 mole = 22.4 Liters gas  1 mole or 22.4 L 22.4 L 1 mole 5.02x10 24 Formula units K 3 PO 4 = 1117.98 g K 3 PO 4

15. Two and Three Step Conversions We Do: How many molecules are in 198.5 grams of sodium chloride? Conversion Factors: 1 mole = formula mass  1 mole or g g 1 mole 1 mole = 6.022 x 10 23  1 mole or 6.022 x 10 23 particles 6.022 x 10 23 1 mole 1 mole = 22.4 Liters gas  1 mole or 22.4 L 22.4 L 1 mole 198.5g NaCl = 2.04x10 24 Formula Units NaCl

16. Two and Three Step Conversions You Do: How many Liters of gas is 3.21 x 10 24 molecules of carbon monoxide? Conversion Factors: 1 mole = formula mass  1 mole or g g 1 mole 1 mole = 6.022 x 10 23  1 mole or 6.022 x 10 23 particles 6.022 x 10 23 1 mole 1 mole = 22.4 Liters gas  1 mole or 22.4 L 22.4 L 1 mole 3.21x10 24 Molecules CO = 119.44 L CO