1. Section 10.1: The Mole (A Measurement of Matter) What is a Mole? A mole is a specific amount of particles. Atoms are very, very, very small. The fact that atoms are so small makes it hard to take measurements (such as mass, volume, density, etc.) of just one atom. So, instead of measuring individual atoms, we will group atoms into what we call a MOLE. 1 Mole = 602 billion trillion atoms or (6.02 x 10 23 atoms) Avogadro’s Number It’s the same as saying: 1 mile = 5,280 feet 1 cup = 8 ounces 1 foot = 12 inches

2. Section 10.1: The Mole (A Measurement of Matter) What is a Mole? Moles don’t always have to be referring to atoms. They can also be referring to molecules, compounds, ions, or other particles. Just remember, 1 mole of anything is equal to 6.02 x 10 23. Question: What number of chloride ions are present if there are 2 moles of chloride ions? 1 mole = 6.02 x 10 23 ions 2 moles of chloride ions x 6.02 x 10 23 chloride ions = 1.204 x 10 24 chloride ions 1 mole of chloride ions

3. Section 10.1: The Mole (A Measurement of Matter) Molar Mass vs. Formular Mass Formula Mass The mass of one compound of Na 2 O Molar Mass The mass of one mole of Na 2 O Na: 23 amu (atomic mass units) O: 16 amu 2 Na = 2 (23 amu) = 46 amu 1 O = 1 (16 amu) = +16 amu 62 amu Note: 1amu = 1.66 x 10 -24 grams 1 mole of Na: 23 grams 1 mole of O: 16 grams 2 moles of Na = 2 (23 g) = 46 grams 1 mole of O = 1 (16 g) = 16 grams 62 grams *We can use our measuring equipment to achieve this value.

4. Section 10.1: The Mole (A Measurement of Matter) Molar Mass vs. Formular Mass So, we realize now that when the atomic mass of an element is reported in AMU’s it is referring to 1 atom of that element. If the mass is reported in grams it is referring to 1mole of atoms of that element. 4 Be 9.012 9.0 grams is the mass of 1 mole of Be atoms.

5. Section 10.1: The Mole (A Measurement of Matter) Molar Mass Determine the molar mass of Copper (II) Chloride. Step 1: Write the compound formula. Step 2: Using the periodic table, write down the molar mass of each element in the compound. (Round the mass to the nearest tenth) Step 3: Add together the molar masses of each element. CuCl 2 63.5 g35.5 gX 2 = 71 g 63.5 g + 71 g = 134.5 grams

6. Section 10.2: Molar Road and Unit Conversions Mole Conversion Chart

7. Section 10.2: Molar Road and Unit Conversions Mole Conversion Chart Particle – Mole Relationship How many atoms of oxygen are in this room if this room contains 0.5 moles of oxygen atoms? Answer:.5 moles O x 6.02 x 10 23 atoms of O = 3.01 x 10 23 atoms 1 mole of O

8. Section 10.2: Molar Road and Unit Conversions Mass – Mole Relationship Determine the mass of 5.5 moles of Potassium Carbonate. K 2 CO 3 (39.1gX 2)12.0g(16.0g X 3) + = 138.2 g X 138.2g K 2 CO 3 5.5 moles K 2 CO 3 1 mole K 2 CO 3 = 760.1 grams K 2 CO 3

9. Section 10.2: Molar Road and Unit Conversions Mass – Particle Relationship Example: Determine the number of molecules of carbon monoxide in 75.0 grams of carbon monoxide. 75.0g CO x 1 mole CO 28.0 grams CO = 2.7 moles COX 6.02 x 10 23 molecules 1 mole CO = 1.6 x 10 24 molecules CO CO 12.0 g16.0g+= 28.0g

10. Section 10.2: Molar Road and Unit Conversions Mole – Volume Relationship Example: Determine the number of molecules of carbon monoxide in 75.0 liters of carbon monoxide at STP. 75.0L CO x 1 mole CO 22.4 liters CO = 3.5 moles COX 6.02 x 10 23 molecules 1 mole CO = 2.1 x 10 24 molecules CO