1. Summary of The Mole

2. Converting from Moles to Number of Particles You Need to Know that: 1 mole = 6 x 10 23 Particles Questions: 1.How many atoms are there in 0.75 moles of Zinc

3. Answer 1. How many atoms are there in 0.75 moles of Zinc 1 mole = 6 x 10 23 Particles 0.75 moles = (6 x 10 23 ) x (0.75) 0.75 moles = 4.5 x 10 23

4. Converting from Number of Particles to Moles You Need to Know that: 6 x 10 23 Particles = 1 Mole Question: How may moles are in a sample of carbon dioxide containing 9 x 10 23 Particles

5. Answer How may moles are in a sample of carbon dioxide containing 9 x 10 23 Particles 6 x 10 23 Particles = 1 mole 9 x 10 23 = 9 x 10 23 6 x 10 23 9 x 10 23 = 1.5 moles

6. Converting from Moles to Litres You Need to Know that: 1 mole = 22.4 L And remember that if you are given an amount in cm 3 you MUST convert to Litres Question: What is the volume in litres at s.t.p. 0.5 moles of oxygen gas

7. Answer What is the volume in litres at s.t.p. 0.5 moles of oxygen gas 1 mole = 22.4 L 0.5 moles = (22.4) x (0.5) 0.5 moles = 11.2 L

8. Converting from Litres to Moles You Need to Know that: 1 mole = 22.4 L And remember that if you are given an amount in cm 3 you MUST convert to Litres Question: How many moles are present in 4.75 litres of NO 2

9. Answer How many moles are present in 4.75 litres of NO 2 22.4 L = 1 mole 4.75 L = 4.75 L 22.4 4.75 L = 0.21 moles

10. How to Calculate Molar Mass You Need to Know that: The molecular mass of an element is found on the periodic table (its the bigger number) The units for molecular mass are gmol -1 Question: What is the molar mass of Cu, Cl 2 and H 2 SO 4

11. Answers 1.Cu = 63.54 gmol -1 2. Cl 2 = 2 x (35.45) = 70.90 gmol -1 3. H 2 SO 4 = (2 x H ) + (1 x S ) + (4 x O) = ( 2 x 1.008)+(1 x 32.06)+(4 x 15.999) = 98.07 gmol -1

12. Converting from Mass to Moles You Need to Know that: 1 mole = molecular mass in grams Question How many moles in 123.7 g of glucose (C 6 H 5 O 6 )

13. Answer How many moles in 123.7 g of glucose (C 6 H 5 O 6 ) Number of moles = Mass of sample Molecular mass of sample You need to find the molecular mass of C 6 H 5 O 6 Molecular mass of C 6 H 5 O 6 = 173 gmol -1 Number of moles = 123.7 173 Number of moles = 0.71 moles

14. Converting from Moles to Mass Question What is the mass of 3.8 moles of glucose (C 6 H 5 O 6 ) You need to rearrange the equation: Number of moles = Mass of sample Molecular mass of sample Mass of sample = Number of moles x Molecular mass of sample Mass of sample = 3.8 moles x 173 gmol -1 Mass of sample = 657.4 g