Presentation is loading. Please wait.

Presentation is loading. Please wait.

It’s time to learn about... Stoichiometry: Conversions At the conclusion of our time together, you should be able to: 1. Convert a mole of a chemical.

Similar presentations


Presentation on theme: "It’s time to learn about... Stoichiometry: Conversions At the conclusion of our time together, you should be able to: 1. Convert a mole of a chemical."— Presentation transcript:

1

2 It’s time to learn about...

3 Stoichiometry: Conversions At the conclusion of our time together, you should be able to: 1. Convert a mole of a chemical to grams of that chemical 2. Convert grams of a chemical to moles of that chemical

4 Interesting Photo:

5 Review of Molar Mass The Mass of 1 mole (in grams) Equal to the numerical value of the average atomic mass (use your periodic table, round to 2 places) 1 mole of C atoms= 12.01 g 1 mole of Mg atoms = 24.31 g 1 mole of Cu atoms = 63.55 g

6 Other Names Related to Molar Mass Molecular Mass: If you have a single molecule, mass is measured in amu’s instead of grams. The molecular mass is the same numerical value as 1 mole of molecules, only the units are different - grams and not amu’s. (This is the beauty of Avogadro’s Number!) Formula Mass: Same goes for ionic compounds. But again, the numerical value is the same, only the units are different.

7 Molar Mass of Molecules and Compounds Mass in grams of 1 mole is equal numerically to the sum of the atomic masses 1 mole of CaCl 2 = 1 mole Ca x 40.08 g/mol + 2 moles Cl x 35.45 g/mol = 110.98 g/mol CaCl 2 1 mole of N 2 O 4 = 92.02 g/mol N 2 O 4

8 “Disorder in the American Courts” These are statements people actually said in court, word for word, taken down and now published by court reporters. ATTORNEY: How can you be so sure, Doctor? WITNESS: Because his brain was sitting on my desk in a jar. ATTORNEY: I see, but could the patient have still been alive, nevertheless? WITNESS: Yes, it is possible that he could have been alive and practicing law.

9 Calculations with Molar Mass molar mass Grams Moles

10 Molar Mass as a Conversion Factor Molar Mass of the Compound 1 mole or 1 mole Molar Mass of the Compound Note that the molar mass could be that of an atom OR a molecule!

11 Calculations with Molar Mass molar mass Grams Moles To convert Grams to Moles: x by 1 mole Molar Mass of the Compound

12 Calculations with Molar Mass molar mass Grams Moles To convert Moles to Grams: x by Molar Mass of the Compound 1 mole

13 Example of Converting Moles to Grams Aluminum is often used for the structure of light-weight bicycle frames. How many grams of Al are in 3.00 moles of Al? 3.00 moles Al ? g Al

14 1. Molar mass of Al1 mole Al = 26.98 g Al 2. Conversion factors for Al 26.98 g Al or 1 mol Al 1 mol Al 26.98 g Al 3. Setup3.00 moles Al x 26.98 g Al 1 mole Al Answer = 80.9 g Al

15 What Do You Call Cheese That Isn't Yours? Nacho Cheese.

16 Stoichiometry: Conversions Let’s see if you can: 1. Convert a mole of a chemical to grams of that chemical 2. Convert grams of a chemical to moles of that chemical

17 Learning Check! The artificial sweetener aspartame (Nutra- Sweet) formula C 14 H 18 N 2 O 5 is used to sweeten diet foods, coffee and soft drinks. How many moles of aspartame are present in 225 g of aspartame?

18 Learning Check! = 0.764 mol 225 g C 14 H 18 N 2 O 5 x 1 mol C 14 H 18 N 2 O 5 294.34 g C 14 H 18 N 2 O 5

19 :Question #1 How many moles of H 2 are in 100.0 g of H 2 ? # mol H 2 = 100.0 g H 2 x 1 mol H 2 2.02 g H 2 = 49.50 mol H 2

20 Question #2 300.0 g of CuSO 4 is needed in an experiment. How many moles does this represent? # mol CuSO 4 = 300.0 g CuSO 4 x 1 mol CuSO 4 159.62 g CuSO 4 = 1.879 mol CuSO 4

21 Question #3 A chemical reaction requires 23.78 moles of silver chloride. How many grams is this? # g AgCl = 23.78 mol AgClx 143.32 g AgCl 1 mol AgCl = 3408 g AgCl

22 Stoichiometry: Conversions At the conclusion of our time together, you should be able to: 1. Convert a mole of a chemical to particles of that chemical 2. Convert particles of a chemical to moles of that chemical

23 Hittite Innovations:

24 Avogadro’s Number as a Conversion Factor 6.02 x 10 23 particles 1 mole or 1 mole 6.02 x 10 23 particles Note that a particle could be an atom OR a molecule!

25 Example of Avogadro’s Number as a Conversion Factor Number of moles of S in 1.8 x 10 24 S atoms 1.8 x 10 24 atoms S x 1 mol S 6.02 x 10 23 atoms S = 3.0 mol S

26 Example of Avogadro’s Number as a Conversion Factor Number of atoms in 0.500 mole of Al = 3.01 X 10 23 atoms Al 0.500 mol Alx 6.02 x 10 23 atoms Al 1 mol Al

27 Stoichiometry: Conversions Let’s see if you can: 1. Convert a mole of a chemical to particles of that chemical 2. Convert particles of a chemical to moles of that chemical

28 #1 Page 9 Number of atoms in 4.50 moles to molecules = 2.71 X 10 24 molecules 4.50 molx 6.02 x 10 23 molecules 1 mol

29 And you thought Chemistry was bad with factor-label problems!!??

30

31 Stoichiometry: Conversions At the conclusion of our time together, you should be able to: 1. Convert a mole of a chemical to particles or grams of that chemical 2. Convert grams of a chemical to moles or particles 3. Convert particles of a chemical to moles or grams 4. Convert particles to grams by going through the mole or the opposite direction.

32 Atoms/Molecules to Grams Since 6.02 X 10 23 particles = 1 mole and 1 mole = molar mass (grams) You can convert atoms/molecules to moles and then moles to grams! (Two step process) You can’t go directly from atoms to grams!!!! You MUST go through MOLES.

33 Calculations molar mass Avogadro’s number Grams Moles particles Everything must go through Moles!!!

34 Flowchart Atoms or Molecules Moles Mass (grams) Divide by 6.02 X 10 23 Multiply by 6.02 X 10 23 Multiply by atomic/molar mass from periodic table Divide by atomic/molar mass from periodic table

35 An Easier Flowchart Atoms or Molecules Moles Mass (grams)

36 I Would Not Suggest Sleep Walking….

37 73 g H 2 O Question How many molecules are in 73 grams H 2 O? # H 2 O molecules = x 1 mol H 2 O 18.02 g H 2 O = 2.4 x 10 24 molecules H 2 O x 6.02 x 10 23 molecules 1 mol H 2 O

38 Atoms/Molecules to Grams How many atoms of Cu are present in 35.4 g of Cu? = 3.35 X 10 23 atoms Cu 35.4 g Cux 1 mol Cu 63.55 g Cu x 6.02 x 10 23 atoms Cu 1 mol Cu

39 Grams to Atoms/Molecules How many grams of Cu are present in 5.4 x 10 23 atoms of Cu? = 57 g Cu 5.4 x 10 23 atoms Cu x 1 mol Cu 6.02 x 10 23 atoms Cu x 63.55 g Cu 1 mol Cu

40 Familiar Saying Pulchritude does not extend below the surface of the derma. Beauty is only skin deep!!

41 Stoichiometry: Conversions Let’s see if you can: 1. Convert a mole of a chemical to particles or grams of that chemical 2. Convert grams of a chemical to moles or particles 3. Convert particles of a chemical to moles or grams 4. Convert particles to grams by going through the mole or the opposite direction.

42 Hittite Innovations:

43 Learning Check! How many atoms of O are present in 78.1 g of oxygen? 78.1 g O 2 1 mol O 2 6.02 X 10 23 molecules O 2 2 atoms O 32.0 g O 2 1 mol O 2 1 molecule O 2 2.94 x 10 24 atoms of O

44 Learning Check for Quiz Tomorrow Prozac, C 17 H 18 F 3 NO, is a widely used antidepressant that inhibits the uptake of serotonin by the brain. What is its molar mass? Add the molar masses of 17 C, 18 H, 3 F, 1 N, 1 O 309.36 g/mol

45 Learning Check #1! What is the mass (in grams) of 1.806 X 10 24 molecules of Fe? 1.806 x 10 24 mc Fe x 1 mol Fe 6.02 x 10 23 mc = 167.6 g Fe x 1 mol Fe 55.85 g Fe

46 Learning Check #3! How many molecules of MgCl 2 are present in 380.84 g of MgCl 2 ? 380.84 g MgCl 2 x 1 mol MgCl 2 95.21 g MgCl 2 = 2.4080 x 10 24 molecules of MgCl 2 x 6.02 x 10 23 mc MgCl 2 1 mol MgCl 2

47

48 Learning Check! How many atoms of K are present in 78.4 g of K? 78.4 g Kx 1 mol K 39.10 g K = 1.21 x 10 24 atoms of K x 6.02 x 10 23 atoms K 1 mol K

49 Learning Check! What is the mass (in grams) of 1.20 X 10 24 molecules of glucose (C 6 H 12 O 6 )? 1.20 x 10 24 mc C 6 H 12 O 6 x 1 mol C 6 H 12 O 6 6.02 x 10 23 mc = 359 g C 6 H 12 O 6 x 1 mol H 2 O 180.18 g C 6 H 12 O 6


Download ppt "It’s time to learn about... Stoichiometry: Conversions At the conclusion of our time together, you should be able to: 1. Convert a mole of a chemical."

Similar presentations


Ads by Google