Presentation is loading. Please wait.

Presentation is loading. Please wait.

The Mole Ch 3.3 and Ch 9.

Similar presentations


Presentation on theme: "The Mole Ch 3.3 and Ch 9."— Presentation transcript:

1 The Mole Ch 3.3 and Ch 9

2 Review (this is a title in your note section)

3 Scientific Notation Scientific Notation—great for very large or very small numbers Ex 1: Hope Diamond has ,000,000,000,000,000,000,000 atoms Ex 2: 1 Carbon atom of the Hope Diamond has a mass of g 4.6 x 1023 atoms = Hope Diamond atoms (not 45 x 1022) 2 x grams = carbon atom mass 4.6 and 2 are the coefficients of the number The 10 to the raised power represents the number of decimal places

4 Convert these to Sci. Notation
3,000,000,000 4500 438,000 0.056 3x109 4.5x103 2.3x10-5 4.38x105 2.45x10-3 5.6x10-2

5 Calculations to practice
Learn how to use your calculator! Calculations to practice (2.3 x 103)(8.2 x 104) = (7.34 x 10-5)(8.221 x 10-2) = 9 x 106 ÷ 4.00 x 103 = 6.23 x x 105 = Think on this…do you need to write down EVERY single number the calculator gives you??? Sig figs! Answer to x 108 x 10-6 x 103 x 105

6 SI Units (Systeme Internationale)
Meter for length Use a meterstick to measure Kilogram for mass (1 kg = 2.2 lbs) Weight is NOT the same thing as mass! Use a scale to measure Kelvin for temperature K = oC + 273 0 K = absolute zero Use a thermometer to measure oC is another option, but not Fahrenheit (in the metric system) Second for time Use a stopwatch to measure Mole for the amount of substance We will talk about mole next chapter Liter for volume Use a graduated cylinder to measure joule or calorie for energy We don’t discuss this much in this class…

7 What is a Conversion Factor?
Conversion factors Values can often be expressed in more than one form $1 = 4 quarters = 10 dimes = 20 nickels = 100 pennies 1 meter = 100cm = 1000mm = 0.001km equal values can be shown as a ratio equal to 1; such ratios are called conversion factors… conversion factors are useful for solving problems in which given measurements must be expressed in some other unit.

8 Dimensional Analysis Dimensional Analysis: a way to problem solve/calculate that uses conversion factors to solve problems. Calculate how many seconds old you are? If you can run the 100 m dash in seconds, how many kilometers per hour is that?

9 Dimensional Analysis Ex: Convert 1,000 kilometers into millimeters.
Ex: A boat is to be three hundred cubits long, fifty cubits wide and thirty cubits high. How big is that in feet? HINT: 1 cubit = 45 cm; 1 foot = 30 cm

10 Need More Problems to Practice?
How many minutes are there in one week? How many seconds are in one year? It takes 12 ounces of sugar to make 1 batch of cookies. How many batches of cookies can be made from a 5 pound bag of sugar?

11 The Mole Ch 3.3 and Ch 9

12 Not talking about these kind of moles…

13 Or these…

14 Measuring Matter We live in a quantitative world… How much? How many?
How much do you make? How old are you? How long is this class? How many questions are on the final exam? How much? How many? We measure by COUNT, MASS, and/or VOLUME.

15 Specific units = specific number
1 pair of shoes = 2 shoes 12 cupcakes =1 dozen cupcakes 1 reem of paper = 500 sheets Each of these could be used as a conversion factor If there are 800 students at LACHSA, how many dozen are there? Calculate it! MOLES is a unit like these…it represents a certain number!!

16 MOLES: measures amount of matter
1 mole = x 1023 of anything Moles are handy when there are large quantities of matter. What if you needed to count the number of grains of sand in 10 grams??? 1 mole of apples = 602,200,000,000,000,000,000,000 apples Thank goodness for scientific notation!  1 mole of $$ = $6.022 x 1023 1 mole of cheerios = x 1023 cheerios

17 A mole is 6.02 x 1023 of anything! A mole of basketballs would just about fit into a ball bag the size of the Earth! So just how big is a mole? Draw a 1 inch square box on your paper: When the teacher says “go” put as many dots in that box as you can in 30 seconds. Now, count the dots. (A highlighter or differently-colored pen may be useful.) x2, What is your dot making rate in dots/minute? _____________ Working at this rate, how many dots could you make in an hour? _____________________ If a student can make 303 dots per minute, it will take 3.78 x 1015 years to make a mole of dots! Even if 25 students in the class worked at this rate, it would take the class x 1014 years, making dots 24-7, to make a mole of dots!

18 More on moles… 6.022x1023 is referred to as Avogadro’s Number
1 mole of Fe atoms = x 1023 atoms 1 mole CO2 molecules= x1023 molecules 1 mol NaCl molecules= x1023 molecules Why the different units for Fe vs. CO2 vs NaCl??

19 One more thing 1 mole =‘s 1 mole of carbon = 12.0 grams 1 mole of Fe = g 1 mole of S = 32.1 g/mol Look at a periodic table, where are these numbers coming from? for our purposes, we will round to 1 decimal place for each atomic mass Atomic mass= mass of 1 mole of the atom Molar mass= atomic number = g/mol Unit can be g or g/mol

20 So just to recap… What is the mass of 1 mole of any element?
it’s atomic mass Where do you find it? Periodic table…(decimal value) What is its unit of measurement? Grams or grams/mol

21 What is the Mass of 1 Mole of a COMPOUND???
To find the mass of 1 mole of a compound, you must know the formula of the compound. Molar masses of chemical compounds = the sums of the molar masses of all the atoms in one molecule of that compound. Ex: calculate the molar mass of 1 mole of carbon dioxide.

22 Molar mass of a compound
Calculate the mass of 1 mole of Sodium Chloride (salt) Gotta know the formula: NaCl Na = 23.0 g x 1 atom in the compound = 23.0 g Cl = 35.5 g x 1 atom in the compound = g Total = = 58.5 g The molar mass of NaCl = 58.5 g 1 mole of NaCl = 58.5 g

23 Example problems: Calculate the molar mass of water.
18.0 g/mol Calculate the mass of 1 mole of PCl3. 137.5 g/mol Calculate the molar mass of Zn(NO3)2. 189.4 g/mol

24

25 Molar Road Map Mole Mass g # of Particles Pg 84 molar mass 1mol _
6.022x1023 atoms Mass g # of Particles (atoms, molecules) 1 mole molar mass 6.022x1023 atoms 1mole Use to convert between mole and mass and amount of particles

26 Molar Road Map Mole Mass g # of Particles Pg 84 molar mass (g) = 1 mol
(atoms, molecules) 1 mol = 6.022x1023 particles Use to convert between mole and mass and amount of particles

27 Converting b/w Moles & Molecules
When we convert moles to: molecules, atoms, formula units, etc, we use the following conversion factors:

28 Ex: moles to particles = 1.20x1024 molecules 2.00 moles x
How many molecules are in 2.00 moles of sucrose? 2.00 moles x = 1.20x1024 molecules

29 Ex: molecules to moles How many moles are in 2.33 x 1024 molecules of water? How many atoms are in 2.95 moles of Au? 3.87 moles 1.77 x 1024

30 Day 2 Warm up: Correct intro to mole worksheet Correct HW
Practice gram to mole Practice gram to particle Chalk activity

31 Molar Road Map Mole Mass g # of Particles Pg 84 molar mass (g) = 1 mol
(atoms, molecules) 1 mol = 6.022x1023 particles Use to convert between mole and mass and amount of particles

32 Converting b/w Moles & Grams (the most common calculation!)
We use molar mass as a conversion factor: Ex: grams to moles Calculate the number of moles in 75.0 g dinitrogen trioxide.

33 Ex: grams to moles Calculate the number of moles in 75.0 g dinitrogen trioxide. Find molar mass of N2O3 Use conversation factor 14.01x x3 = 76.02g/mole 1 mole 76.02g 75.0g x = .986mol N2O2

34 Mole  Mass You need 3.0 moles of NaCl for a lab experiment.
The molar mass can be used to convert between mass and moles. Need to be able to go both ways…from moles to mass or mass to moles. You need 3.0 moles of NaCl for a lab experiment. How are you going to measure out 3.0 moles? Can’t do it on a scale… You need to convert from moles to grams. In order to convert, you need to know the mass of 1 mole of NaCl Now solve…

35 1s2 2s2 2. 1s2 2s2 2p3 3. 1s2 2s2 2p6 3s2 3p6 4s2 3d8 (or 1s2 2s2 2p6 3s2 3p6 3d8 4s2)
4. 1s2 5. 1s2 2s2 2p6 3s2 3p4

36 Ex: moles to grams Calculate the mass, in g, of moles of sodium chloride. Calculate the number of moles in 75.0 g of nitrogen gas. 14.36 g NaCl = 57.45g/mol

37 Review: Moles of …. How much is ONE mole of Zinc Water (H2O) NaCl
Chromium Magnesium Sodium Bicarbonate Hydrogen peroxide carbon

38 The mole is a unit Mole song Boseman:
https://www.youtube.com/watch?v=xPdqEX_ WMjo

39 Molar Road Map Mole Mass g # of Particles Pg 84 molar mass (g) = 1 mol
(atoms, molecules) 1 mol = 6.022x1023 particles Use to convert between mole and mass and amount of particles

40 Problems to Practice How many molecules are in 1.14 moles of SO3?
(6.87 x 1023 atoms) Calculate the mass in grams of 2.50 moles of Iron (II) Hydroxide. (Who remembers how to write this formula???) (225 grams) Fe(OH)₂

41 Problems to Practice 3. If you have 7.31 grams of CuSO4, how many moles is this? ( moles) 4. How many moles are in 4.65 x molecules of NO2 Is this a 1 step or 2 step problem??? (0.772 moles)

42 Molar Road Map Mole Mass g # of Particles Pg 84 molar mass 1mol _
6.022x1023 atoms Mass g # of Particles (atoms, molecules) 1 mole molar mass 6.022x1023 atoms 1mole Use to convert between mole and mass and amount of particles

43 Molar Road Map Mole Mass g # of Particles Pg 84 1 mol = molar mass
(atoms, molecules) 1 mol = 6.022x1023 Use to convert between mole and mass and amount of particles

44 Convert both ways (notes cont.)
1. Find the mass, in grams of 4.52 x molecules of C20H42? (212 grams) 2. Find the number of atoms in 75.0 g of dinitrogen trioxide? Molar mass = 76.0g/mol, 5.94x1023 atoms 3. How many grams are there in 2.80 x atoms of silicon? Don’t forget your sig.figs! 4.65x28.1g = 131g 4. How many grams is 2.7 x 1023 molecules of Br2? 71.6 = 72g

45 Warm up How many molecules are in 1.14 moles of SO3?
(6.87 x 1023 molecules) Calculate the mass in grams of 2.50 moles of Iron (II) oxide. 179.8 g How many grams are there in 2.80 x atoms of N2? Don’t forget your sig.figs! 4.65x28.1g = 131g Fe(OH)₂

46 Turn in warm ups and Mole worksheet!
Mole notes continued…

47 Notice the difference? How many moles are there in 2.80 x 1024 atoms of silicon? Don’t forget your sig.figs! How many moles is 2.7 x 1023 molecules of Br2? NOTICE: how we calculated for atoms when talking about an element and molecules when talking about a compound? Can you calculate atoms for a compound? Could you calculate atoms of Br2? YES, but that is not a single step problem… …see next slide 

48 Number of atoms in a compound
Often multiple conversion factors are needed. Like if you need to convert your age to seconds… Go from years to months to days to hours to sec. 1. How many ATOMS of propane (a covlnt cmpd!!) are in 2.12 moles of propane (C3H8)? Why can you NOT go straight from moles to atoms in this problem? = 1.28x1024 C3H8 molecules 2.12 moles x 11 atoms per molecules (1.28x1024) x 11 = 1.40 x1025 atoms

49 Number of atoms in a compound
How many ATOMS of Carbon are in moles of propane (C3H8)? = 1.28x1024 C3H8 molecules 2.12 moles x (1.28x1024) x 11 = 1.40 x1025 atoms 11 atoms per molecules 3/11 of atoms are C 3/11 (1.40 x1025 ) = C atoms

50 Molecules vs atoms How many molecules are in 1.14 moles of SO3?
(6.87 x 1023 molecules) How many atoms are in 1.14 moles of SO3? (2.75 x 1024 atoms) 5. How many atoms are in 1.09 x 1024 molecules of water? 6. How many atoms of hydrogen in 2,560 atoms of water? 7. How many atoms of hydrogen in 1.50 moles of water?

51 Molar mass What is the molar mass of 1 mole of lithium?
What is the molar mass of 1 mole of carbon dioxide? What is molar mass of 35 grams of .5 mole of aluminum? What is the molar mass of 10 moles of sodium that has a mass of 220 grams.

52 Use the mole map to solve:
How many moles are in g of H2O? How many molecules are in moles of H2O? How many atoms are in 1.09 x molecules of water? What is the mass in grams of 7.23 x molecules of sucrose (C12H22O11)?

53 Warm ups #2 How many atoms of oxygen in 3.00 moles of carbon dioxide?
How many atoms of hydrogen in grams of H4CO

54

55 Chapter Goals: The Road Map
Volume (L) The MOLE Molecules, atoms, formula units Mass (g)

56

57 Molar Road Map Volume L Mole Mass g # of Particles Pg 84 1 mole 22.4 L
molar mass 1mole Mole 1mol _ 6.022x1023 atoms Mass g # of Particles (atoms, molecules) 1 mole molar mass 6.022x1023 atoms 1mole

58 Molar Road Map Volume L Mole Mass g # of Particles Pg 84
1 mol = molar mass Mass g # of Particles (atoms, molecules) 1 mol = 6.022x1023

59 Mole-Volume Relationship
For gases, Avogadro (in 1811) proposed a significant relationship that stated that: equal volumes of gases at the same temperature and pressure contain equal numbers of particles. Particle size varies for different gases but because particles are so spread out, they do not take up any greater amount of space. Temp has an effect on volume As temp. increases, volume increases Pressure also has an effect on volume As pressure increases, volume decreases STP = Standard Temperature and Pressure Temp = 0 degrees C & pressure = 1 atm

60 Converting b/t Moles & Volume
MOLAR VOLUME = 22.4 L/mol (the volume of one mole of a gas) One mole of ANY gas will expand to have a volume of 22.4 L at STP. STP = Standard Temperature and Pressure Standard Temp: 0 degrees C Standard Pressure: 1 atm

61 Molar Volume Example The conversion factors (always):
1. How many moles of N2 are in 120 L of gas? 1mol 22.4L 120L x = 5.36 mol N2 Can you then calculate the mass?

62 Molar Road Map Volume L Mole Mass g # of Particles Pg 84
1 mol = molar mass Mass g # of Particles (atoms, molecules) 1 mol = 6.022x1023

63 More examples: mole and volume
2. What is the volume of 2.54 moles of methane gas? 56.9L 3. How many moles are in 6.00 L of H2 gas? .268mol .3mol 4. How many grams are in 12 L of O2 gas? 17.1g= 17g 5. How many L of oxygen gas (at STP) are in 6.5 x molecules of oxygen gas? 242L = 240 L

64 Density= mass/ volume or D= g/L
6. The density of a gas at STP is g/L. What is the molar mass of the gas? 7. What gas is it? neon 8. What is the density of 1.00 mole of helium gas? g L L mole = 20.2 g/mol x 4.00 g/mol x 1mol/22.4 L = .179 g/L

65 Summary Follow the road map! Moles  L or L moles: molar volume
Moles  g or g  moles: molar mass

66 More Problems to Practice
0.6 moles of SO2 is produced when coal is burned. How many liters of gas at STP is this? At STP, what volume does 1.25 moles of He occupy? 74.5 liters of CO2 at STP is contained in a flask. How many moles is this? The density of a gas at STP is g/L. What is the molar mass of the gas? What is the density of krypton gas at STP?

67 Molar Road Map: Title Moles (in the middle) Particles Mass Volume
In your Chemistry Notebook, classwork sections: Create your own molar road map including pictures and conversation factors. Be creative and use color. Include the following: Title Moles (in the middle) Particles Mass Volume Arrows between each unit (3 total) Conversion factors between each unit (3 total) A picture to represent each unit (4 total) Color for emphasis

68 End day

69 Warm up At STP, what volume does 1.75 moles of He occupy?
What would be the volume of 8.00g of helium of STP? What is the density of He at STP? 39.2L 44.8L 4.0g/mol x 1mol/22.4L = .179g/L

70 Stoichiometry The recipe of chemistry

71 Analogy Suppose you are preparing a cake. Each Cake (Ck) requires 1.0 cake mix (Cm), 0.5 cup of oil (Oi), 1.0 cup of water (Wa) and 2.0 eggs (Eg). Write the balanced equation for making: 1 ________ ________ + 1________ 2 _______ 1 ________ 1.0 cake mix cups oil cup water + 2 eggs  1.0 cake How much is left over?

72 1.0 cake mix + 0.5 cups oil + 1.0 cup water + 2 eggs  1.0 cake
Calculating Cakes Calculate the number of cakes (Ck) that can be made from 12 cake mixes (Cm) 12Cm x 1 Ck = 12 Ck 1 Cm Calculate the number of cakes (Ck) that can be made from 10.0 cups of oil (Oi) 10.0 Oi x 1 Ck = 20 Ck 0.5Oi If you need to make 29 cakes (Ck), how many eggs (Eg) do you need? 29 Ck x 2 Eg = 58 Eg 1 Ck

73 USING EQUATIONS Equations are a chemist’s recipe.
Stoichiometry: the calculation of quantities in chemical reactions Equations are a chemist’s recipe. Eqs tell chemists what amounts of reactants to mix and what amounts of products to expect. When you know the quantity of one substance in a rxn, you can calculate the quantity of any other substance consumed or created in the rxn.

74 Why should you care? Nearly everything we use is manufactured from chemicals. Soaps, shampoos, conditioners, CD’s, cosmetics, medications, clothes. For a manufacturer to make a profit the chemical processes carried out in industry must be economical A balanced equation is needed and used so chemicals are not wasted when making products

75 Reading Chemical Equations
How would you read: N2 (g) + H2 (g)  NH3 (g) Balance and read: N2 (g) + 3H2 (g)  2NH3 (g) Coefficients can represent different possible units Atoms/molecules Moles Mass in grams Mass of reactants equals mass of products Law of Conservation of mass Liters (if compound is a gas at STP)

76 N2 + 3H2  2NH3 1 mol N2 + 3 mol N2  2 mol NH3 28.0 g N2 +
3 (2.0 g H2) 2 (17.0 g NH3) 34.0 g reactants 34.0 g products + 22.4 L 22.4 L 22.4 L 22.4 L N2 67.2 L H2 44.8 L NH3

77

78 MOLE ratios What are the possible mole ratios in:
N2 (g) + 3H2 (g)  2NH3 (g) 1 mole of N2 reacts with 3 moles of H2 to produce 2 moles of NH3. Possible mole ratios for this formula: 1N2 1N2 3H2 3H2 2NH3 2NH3 Reaction to form ammonia in this 1:3:2 ratio. Mole ratios are CONVERSION FACTORS! Once you have the ratios, you can perform calcs. (a.k.a. STOICHIOMETRY)

79 Conversion of Quantities in Moles
Mole ratio: from balanced equation Amount of given (mol) Amount of unkown (mol) Mole unknown Mole given X = Ex: How many moles of water are produced from 5.80 moles of oxygen gas? O2 + H2  H2O O2 + 2H2  2H2O 5.80mole O2 x Write equation Balance! Set up conversion factor 2 mol H2O 1 mol O2 11.6 moles water

80 N2 (g) + 3H2 (g)  2NH3 (g) 1. How many moles of ammonia are produced from moles of N2? (1.2 mol NH3) 2. How many moles of H2 are needed to react with moles of N2 gas? (1.29 mol H2) 3. How many moles of H2 are needed to produce moles of ammonia (NH3)? (2.97 mol H2)

81 from balanced equation
Mole ratio: from balanced equation Amount of given (mol) Amount of unkown (mol) Mole unknown Mole given X = 4. Ammonia, NH3 is a widely used fertilizer and used in household cleaners. How many moles of ammonia are produced when 6 mol of H gas react with excess nitrogen gas? 4 mol NH3 5. The decomposition of potassium chlorate, KClO3 into potassium chloride and oxygen gas is used as a source of oxygen in the lab. How many moles of potassium chlorate are needed to produce 15 mol of oxygen gas? Write equation Balance! Set up conversion factor 10 mol KClO3

82 Ch 9.1 Historical Chemistry: pg 303, #1-2

83 End day

84 Warm up How many moles of SnF2 will be produced by 12.5 moles of HF?
Sn + 2HF  SnF2 + H2 How many moles of SnF2 will be produced by 12.5 moles of HF? How many moles HF are needed to produce 6.85 moles of SnF2?

85 Calculating using MASS quantities
No lab balance measures moles directly, instead grams is a more practical unit. To calculate grams: 1. convert to moles first, then grams Using our same example, you can calculate how many grams of each compound: N2 (g) + 3H2 (g)  2NH3 (g) REMEMBER: when you use a gram/mole conversion factor: 1 mol = molar mass 3.00 g N2 x x x 1 mol 28g 2 mol NH3 1 mol N2 17 g 1 mol

86 PARTICLES B MOLE 6.02X10 A 22.4 L 23 MASS VOLUME MOLE MAP MOLAR MASS RATIO

87 Conversion of amount in Moles & Mass
6.022x1023 Particle A 6.022x1023 Particle B Mole A Mole B Mass A Molar Mass Mole Ratio Molar Mass Mass B Volume A 22.4 L 22.4 L Volume B Ex 1: What mass, in grams, of glucose is produced when 3.00 mol of water reacts with excess carbon dioxide to produce glucose and oxygen? 6CO2 + 6H2O  C6H12O6 + 6O2 3.00mol x x Write equation Balance! Set up conversation factor 1 mol glucose g 6 mol water mole 90.1g glucose

88 examples Particle A Mass A Volume A Particle B Mass B Volume B Mole A Mole B 6.022x1023 Molar Mass 22.4 L Mole Ratio What mass of carbon dioxide is needed to react with 3.00 mol water? How many moles of H2O are formed from a reaction using 824g NH3 is the reaction: NH3 + O2  NO + H2O (unbalanced) 4NH3 + 5O2  4NO + 6H2O 132g CO2 6CO2 + 6H2O  C6H12O6 + 6O2 72.5 mol H2O

89 Conversion of amount: Mass to Mass
Particle A Mass A Volume A Particle B Mass B Volume B Mole A Mole B 6.022x1023 Molar Mass 22.4 L Mole Ratio Ex 4: How many grams of SnF2 are produced from the reaction of 30.00g HF with Sn. Sn(s) + 2HF(g)  SnF2(s) +H2(g) 30.00g HF x x x 5. How many grams of NH4NO3 are required to produce 33.0g N2O? (the laughing gas needed for an anesthetic in dentistry) NH4NO3(s)  N2O(g) + 2H2O(l) 1 mol HF 20.0 g HF 1 mol SnF2 2 mol HF 156.7g SnF2 1 mol SnF2 117.5g SnF2 60.0g NH4NO3 6. How many molecules of oxygen gas are produced when 29.2 g of water is decomposed? (4.88 * 1023 molecules of O2)

90 More Problems to Practice
Carbon dioxide is produced from the synthesis of oxygen gas with carbon monoxide. Write and balance this chemical equation and then tell how many liters of oxygen gas are required to burn 3.86 liters of carbon monoxide. Assume STP. (1.93 L O2) 2. How many grams of NH4NO3 are required to produce 33.0g N2O? (the laughing gas needed for an anesthetic in dentistry) NH4NO3(s)  N2O(g) + 2H2O(l) 3. How much water in grams is produced in this reaction? 60.0g NH4NO3 27.0g H2O

91 Stoichiometry Practice
Answer in classwork section of notebook: N2 (g) + 3H2 (g)  2NH3 (g) Calculate the number of grams of ammonia produced by the reaction of 5.40 g of H2 with N2. (30.6 g NH3) Calculate the number of liters of N2 needed in order to react with 0.78 moles of H2. (5.8 L N2) Calculate the grams of N2 needed in order to produce x 1023 molecules of NH (21.5 g N2) Particle A Mass A Volume A Particle B Mass B Volume B Mole A Mole B 6.022x1023 Molar Mass 22.4 L Mole Ratio

92 Stoichiometry Practice
Answer in classwork section of notebook: N2 (g) + 3H2 (g)  2NH3 (g) Calculate the number of grams of ammonia produced by the reaction of 5.40 g of H2 with N2. (30.6 g NH3) Calculate the number of liters of N2 needed in order to react with 0.78 moles of H2. (5.82 L N2) Calculate the grams of N2 needed in order to produce x 1023 molecules of NH3. (21.5 g N2) Ch 9.2: Answer #2-4 on page 311

93 MOLE-MOLE RATIO You will ALWAYS use the new MOLE-MOLE ratio step to get you from where you are to where you are are going. Particle A Mass A Volume A Particle B Mass B Volume B Mole A Mole B 6.022x1023 Molar Mass 22.4 L Mole Ratio

94 More Problems to Practice
Carbon dioxide is produced from the synthesis of oxygen gas with carbon monoxide. Write and balance this chemical equation and then tell how many liters of oxygen gas are required to burn 3.86 liters of carbon monoxide. Assume STP. (1.93 L O2)

95 Problems to Practice Aluminum reacts with oxygen to produce Aluminum Oxide. How many moles of aluminum are needed to form 3.7 moles of Aluminum Oxide? Write the balanced equation and solve. (7.4 mol Al)

96 More Problems to Practice
How many molecules of oxygen gas are produced when g of water is decomposed? The balanced chemical equation is given for you. Use your new mole map to solve. 2H2O –electricity 2H2 + O2 (4.88 * 1023 molecules of O2) How many molecules of oxygen are produced by the decomposition of 6.54 g of Potassium Chlorate? The balanced chemical equation is given for you. Use your new mole map to solve. 2KClO3  2KCl + 3O2 (4.82 * 1022 molecules of O2)

97 Even More Problems Sodium hydroxide reacts with Sulfuric acid to produce water and Sodium Sulfate. Calculate the amount of water (in grams) that would be produced from g of the acid. (15.0 g H2O) In a combustion reaction, C2H4 reacts with oxygen to produce H2O and CO2 in the following reaction. Balance it and then determine the amount of oxygen (in grams) that is consumed if 2.69g of water is produced. _____C2H4 + _____O2  _____CO2 + _____H2O (7.17 g O2)

98 Mole to mass Mass to mole Amount of given (mol) mass of unkown (g)
Mole ratio: (balanced equation) Molar mas: (periodic table) Amount of given (mol) mass of unkown (g) X x = Mole unknown molar mass unknown(g) Mole given 1 mole unkown Mass to mole Mole ratio: (balanced equation) Molar mas: (periodic table) Mass of given (g) Amount unkown (mol) X x = 1 mole given mol unknown molar mass mol given given (g)

99 Mass to mass mass of unknown (g) Mass of given (g) X x X =
1 mole given mol unknown mole mass molar mass mol given mol given (g) unknown X x X =

100 End day

101 Warm up Carbon dioxide is produced from the synthesis of oxygen gas with carbon monoxide. Write and balance this chemical equation and then tell how many liters of oxygen gas are required to burn liters of carbon monoxide. Assume STP. (1.93 L O2) Particle A Mass A Volume A Particle B Mass B Volume B Mole A Mole B 6.022x1023 Molar Mass 22.4 L Mole Ratio

102 Theoretical yield vs Actual yield: Ch 9.3
The difference in the optimal, expected outcome and the actual tested outcome Experimentation is not perfect Not all reactant are react so some may be left over Conditions may not be perfect for a full reaction

103

104 How many sandwiches, how much excess?

105 Limiting Reagent Limiting reagent: reactant that determines the amount of product that can be produced. It limited… Excess reagent: reactant that is not used up in the reaction - there is more available than needed Steps to determine LR Calculate theoretical yield (g or mol) Determine limited reagent Use the original actual yield of the limiting reactant to calculate product produced (in moles or grams)

106 Demo 25ml Which system will produce the most CO2 product? Flask 1 2 3
4 5 6 Volume acetic acid (mL) 25ml Sodium bicarbonate (g) 0.50g 1.00g 1.50g 2.00g 2.50g 3.00g Which system will produce the most CO2 product?

107 Problems to Practice C2H4 + 3O2  2H2O + 2CO2
Ex 1. Given the following balanced equation, determine which is the LR if 2.70 moles of C2H4 is reacted with 6.30 moles of O2. C2H4 + 3O2  2H2O + 2CO2 (O2 is LR) 2. Using the info gathered from above, calculate the GRAMS of water that will be produced. 75.6 g H2O 2 mole H2O 1 mole C2H4 2.70 mol C2H4 x = 5.4 mol H2O 2 mole H2O 3 mole O2 6.30 mol O2 x = 4.20 mol H2O Less= limiting reagent=O2 4.20mol x 18g/mol =

108 More Problems to Practice
3. Identify the LR when 6.00 g HCl reacts with g Mg in the following reaction: Mg + 2HCl  MgCl2 + H2 (HCl is LR) 4. Using the info gathered from above, calculate the GRAMS of hydrogen gas that will be produced. (0.164 g H2)

109 Percent Yield theoretical yield % yield = ____actual yield___ x 100
measure of the efficiency of a reaction carried out in lab. Actual yield would be given in problem or determined from actually performing the lab. Theoretical yield can be calculated using the Limiting Reagent.

110 Percent Yield: Problem to Practice
If 15.0 g of nitrogen gas reacts with 15.0 g of hydrogen gas, 10.5 g of ammonia (NH3) is produced. Calculate the percent yield. N2 yields 1.07 mol NH2 H2 yields 5.0mol NH2 Limiting reactant: N2 (theoretical yield: 18.2 g NH3) (percent yield: 57.7%) % yield = ____actual yield___ x 100 theoretical yield Balance chemical equation Find limiting reactant Calculate theoretical yield Find percent yield

111 I’m not sure I’ve got this….

112 Calculate the number of moles in 9. 023 x 1023 molecules of NO2. (6
Calculate the number of moles in x molecules of NO2. (6.48 moles) Calculate the volume of 2.30 moles of SO2 gas at STP. (51.5 L) Find the molar mass of B2(SO3) g/mol

113 Common Core Standards HS-PS1-7. Use mathematical representations to support the claim that atoms, and therefore mass, are conserved during a chemical reaction. HS-PS1-6. Refine the design of a chemical system by specifying a change in conditions that would produce increased amounts of products at equilibrium. HS-PS1-5. Apply scientific principles and evidence to provide an explanation about the effects of changing the temperature or concentration of the reacting particles on the rate at which a reaction occurs. HS-PS1-3. Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.

114 Common Core Standards HS-PS1-7. Use mathematical representations to support the claim that atoms, and therefore mass, are conserved during a chemical reaction. CA State Standards D2. Investigate quantitative relationships in chemical reactions, and solve related problems; D3. Demonstrate an understanding of the mole concept and its significance to the quantitative analysis of chemical reactions.

115 Common Core Standards HS-PS1-6. Refine the design of a chemical system by specifying a change in conditions that would produce increased amounts of products at equilibrium.

116 Common Core Standards HS-PS1-5. Apply scientific principles and evidence to provide an explanation about the effects of changing the temperature or concentration of the reacting particles on the rate at which a reaction occurs.

117 Common Core Standards HS-PS1-3. Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.


Download ppt "The Mole Ch 3.3 and Ch 9."

Similar presentations


Ads by Google