1. AP Chem Catalyst AP Chem Catalyst Catalyst Questions To Do & Homework

2. Conversion Factors To convert from one unit to another we use a conversion factor.

3. I. Conversion Factors Units You Want Units You Have Number with units given New number with New Units

4. Conversion Factors Example – Convert $15 to cents 100Cents 1 Dollars 15 Dollars 1500 ¢

5. Multi-Step Conversions We may need to take multiple steps to convert between units. We must set up a series of conversion factors so that all unnecessary units cancel one

6. Convert 3 hours to seconds 1 hour 3 hours 10,800 sec 60 min 1 min 60 sec

7. Table Talk How many days are there in 525,000 seconds? (Note – 1 day = 24 h, 1 h = 60 min, and 1 min = 60 s)

8. White Board Races

9. Question 1 Convert 500 minutes into seconds

10. Question 2 You have 5 dozen doughnuts, how many doughnuts do you have (12 doughnuts = 1 dozen)

11. Question 3 You have 14 cups of water, how many gallons of water do you have (1 gallon = 4 quarts; 1 quart = 4 cups)

12. Question 4 You have 32 cups of solution. How many gallons do you have? (1 gallon = 4 quarts; 1 quart = 4 cups)

13. Question 5 How many minutes are there in 1 year?

14. Question 6: 1.You have 42 dollars. You know the following conversions: 1 pound = $1.62 1 pound = 1.25 Euro How many Euros do you have?

15. How High Can You Count? 602,200,000,000,000,000,00 0,000

16. Atoms, ions, and molecules are so small, that a grain of carbon may have over trillions of atoms/particles. to make counting large numbers easier, scientist use the mole.

17. What is the mole?

20. The Mole The mole is a unit that describes the amount of particles that a substance has. Just like 1 dozen = 12 eggs, 1 deck = 52 card: 1 mole = 6.02 x 10 23 particles Avogadro’s Number

21. It’s a conversion factor! 6.022 x 10 23 particles mole

22. What does 1 mole look like?

23. He observed that The # of C atoms in exactly 12 grams of Carbon-12 had 6.02 x 10 23 atoms, so he let 1 mole of any substance = 6.02 X 10 23 particles/ions/atoms/compounds/ions How did Amedeo Avogadro come up with this conversion factor or relationship for counting particles?

24. Get it? 1 mole of C = 6.02 x 10 23 C atoms 1 mole of H 2 O = 6.02 x 10 23 H 2 O molecules 1 mole of Skittles = 6.02 x 10 23 skittles 1 mole of electrons = 6.02 x 10 23 electrons

25. What does 1 mole look like?

26. Example 1 How many atoms are there 2.66 moles of sulfur? Hint: You will be using avogadro’s number b/c you want # of particles (atoms).

27. Example 2 Find the # of molecules in 2.5 moles of sulfur dioxide (S0 2 )

28. What does all this mean? Don’t just do the math. 2.5 moles of SO 2 is like saying one dozen. 1 mole of any substance has 6.022 X 10 23 molecules 2.5 moles of SO 2 has 1.5 X 10 24 molecules. Chemists can’t deal with 1.5 X 10 24 molecules, it’s too large so we convert it into a smaller number.

29. Example 3 How many moles are in 2.54 X 10 22 Fe 3+ cations?

30. You try these on line paper 4) How many ions are there in 0.187 moles of Na+ cations? Answer: 1.13 X 10 23 ions 5) How many atoms are there in 1.45 X 10 -17 moles of arsenic? Ans: 8.73 X 10 6 atoms 6) How many compounds in 4.224 moles of acetic acid, C 2 H 4 O 2 ? Ans: 2.54 X 10 24 acetic acid compounds 7) How many moles of xenon does 5.66 X 10 23 atoms have? Ans: 0.94 moles of Xe 8) A sample of SO 2 has 3.01 X 10 23 molecules, how many moles is this? Ans: 0.5 mol SO 2

31. Moles can be converted to mass

32. Molar Mass Molar mass is the mass, in grams, of 1 mole of substance. The molar mass is equal to the mass listed on the periodic table Units of Molar mass are g/mol Molar Mass Molar mass of carbon is 12 g / mol Means 1 mol of C has 12 grams

33. Example 9… What is the molar mass of Thorium? What does that mean?

34. Molar mass of Th = 232 g/ mol 1 mole of Th has 232 grams

35. You can find the mass from moles or # of particles Example 10: You have 2.44 X 10 24 atoms of carbon whose molar mass is 12.01g/mol according to your PT. A)How many grams of carbon is that?

36. Example 11: Find the mass of each substance in grams: A)2.11 x 10 24 atoms of copper

37. You try - Example 12: Find the mass of each substance in grams: 3.99 x 10 25 molecules of methane, whose MM = 16 g/mol

38. Example 13: You find the molar mass of an element using the atomic mass but what if you have a compound like glycerol, C 3 H 8 O 3

39. You Try - Example 14: Use the answer from Ex 13 to find the amount of molecules in 47.5 g of glycerol.

40. Example 15: Find the molar mass of ZnCl 2

41. You try - Example 16: Find the molar mass of (NH 4 ) 2 SO 4

42. Exit Slip (10 min) A)Find the molar mass of toluene, C 6 H 5 CH 3. B)Find the # of moles in 7.51 g of toluene C)How many covalently bonded compounds are found in 5 grams of toluene?