stoichiometry
TRANSCRIPT
1
CHAPTER THREE
CHEMICAL EQUATIONS & REACTION STOICHIOMETRY
2
Chapter Three Goals
1. Chemical Equations2. Calculations Based on Chemical Equations3. The Limiting Reactant Concept4. Percent Yields from Chemical Reactions5. Sequential Reactions6. Concentrations of Solutions7. Dilution of solutions8. Using Solutions in Chemical Reactions9. Synthesis Question
3
Chemical Equations
Symbolic representation of a chemical reaction that shows:
1. reactants on left side of reaction
2. products on right side of equation
3. relative amounts of each using stoichiometric coefficients
4
Chemical Equations
Attempt to show on paper what is happening at the laboratory and molecular levels.
5
Chemical Equations
Look at the information an equation provides:
Fe O + 3 CO 2 Fe + 3 CO2 3 2
6
Chemical Equations
Look at the information an equation provides:
reactants yields products
Fe O + 3 CO 2 Fe + 3 CO2 3 2
7
Chemical Equations
Look at the information an equation provides:
reactants yields products
1 formula unit 3 molecules 2 atoms 3 molecules
Fe O + 3 CO 2 Fe + 3 CO2 3 2
8
Chemical Equations
Look at the information an equation provides:
reactants yields products
1 formula unit 3 molecules 2 atoms 3 molecules
1 mole 3 moles 2 moles 3 moles
Fe O + 3 CO 2 Fe + 3 CO2 3 2
9
Chemical Equations
Look at the information an equation provides:
reactants yields products
1 formula unit 3 molecules 2 atoms 3 molecules
1 mole 3 moles 2 moles 3 moles
159.7 g 84.0 g 111.7 g 132 g
Fe O + 3 CO 2 Fe + 3 CO2 3 2
10
Chemical Equations
Law of Conservation of Matter – There is no detectable change in quantity of matter in an
ordinary chemical reaction.– Balanced chemical equations must always include the same
number of each kind of atom on both sides of the equation.– This law was determined by Antoine Lavoisier.
Propane,C3H8, burns in oxygen to give carbon dioxide and water.
OH 4 CO 3 O 5 HC 22283
11
Law of Conservation of Matter
NH3 burns in oxygen to form NO & water
You do it!You do it!
12
Law of Conservation of Matter
NH3 burns in oxygen to form NO & water
OH 6 + NO 4 O 5 + NH 4
correctlyor
OH 3 + NO 2 O + NH 2
223
2225
3
13
Law of Conservation of Matter
C7H16 burns in oxygen to form carbon dioxide and water.
You do it! You do it!
14
Law of Conservation of Matter
C7H16 burns in oxygen to form carbon dioxide and water.
OH 8 + CO 7 O 11 + HC 222167
15
Law of Conservation of Matter
C7H16 burns in oxygen to form carbon dioxide and water.
Balancing equations is a skill acquired only with lots of practice– work many problems
OH 8 + CO 7 O 11 + HC 222167
16
Calculations Based on Chemical Equations
Can work in moles, formula units, etc. Frequently, we work in mass or weight (grams
or kg or pounds or tons).
Fe O + 3 CO 2 Fe + 3 CO2 3 2
17
Calculations Based on Chemical Equations
Example 3-1: How many CO molecules are required to react with 25 formula units of Fe2O3?
CO of molecules 75
unit formula OFe 1
molecules CO 3OFe units formula 25 = molecules CO ?
3232
18
Calculations Based on Chemical Equations
Example 3-2: How many iron atoms can be produced by the reaction of 2.50 x 105 formula units of iron (III) oxide with excess carbon monoxide?
325 OFe units formula 102.50=atoms Fe ?
19
Calculations Based on Chemical Equations
Example 3-2: How many iron atoms can be produced by the reaction of 2.50 x 105 formula units of iron (III) oxide with excess carbon monoxide?
OFe units formula 1
atoms Fe 2
OFe units formula 102.50=atoms Fe ?
32
325
20
Calculations Based on Chemical Equations
Example 3-2: How many iron atoms can be produced by the reaction of 2.50 x 105 formula units of iron (III) oxide with excess carbon monoxide?
atoms Fe 105.00 OFe units formula 1
atoms Fe 2
OFe units formula 102.50=atoms Fe ?
5
32
325
21
Calculations Based on Chemical Equations
Example 3-3: What mass of CO is required to react with 146 g of iron (III) oxide?
32
3232 OFe g 7.159
OFe mol 1OFe g 146 = CO g ?
22
Calculations Based on Chemical Equations
Example 3-3: What mass of CO is required to react with 146 g of iron (III) oxide?
3232
3232 OFe mol 1
CO mol 3
OFe g 7.159
OFe mol 1OFe g 146 = CO g ?
23
Calculations Based on Chemical Equations
Example 3-3: What mass of CO is required to react with 146 g of iron (III) oxide?
CO g 8.76CO mol 1
CO g 28.0
OFe mol 1
CO mol 3
OFe g 7.159
OFe mol 1OFe g 146 = CO g ?
3232
3232
24
Calculations Based on Chemical Equations
Example 3-4: What mass of carbon dioxide can be produced by the reaction of 0.540 mole of iron (III) oxide with excess carbon monoxide?
OFe mol 1
CO mol 3OFe mol 540.0CO g ?
32
2322
25
Calculations Based on Chemical Equations
Example 3-4: What mass of carbon dioxide can be produced by the reaction of 0.540 mole of iron (III) oxide with excess carbon monoxide?
2
2
32
2322 CO mol 1
CO g 0.44
OFe mol 1
CO mol 3OFe mol 540.0CO g ?
26
Calculations Based on Chemical Equations
Example 3-4: What mass of carbon dioxide can be produced by the reaction of 0.540 mole of iron (III) oxide with excess carbon monoxide?
? g CO mol Fe O3 mol CO
1 mol Fe O
g CO
mol CO
= 71.3 g CO
2 2 32
2 3
2
2
2
0 54044 0
1.
.
27
Calculations Based on Chemical Equations
Example 3-5: What mass of iron (III) oxide reacted with excess carbon monoxide if the carbon dioxide produced by the reaction had a mass of 8.65 grams?
You do it!You do it!
28
Calculations Based on Chemical Equations
3232
32
2
32
2
2232
O Feg 5.10O Femol 1
O Feg 7.159
CO mol 3
O Femol1
CO g 44.0
molCO 1CO g 8.65O Feg ?
Example 3-5: What mass of iron (III) oxide reacted with excess carbon monoxide if the carbon dioxide produced by the reaction had a mass of 8.65 grams?
29
Calculations Based on Chemical Equations
Example 3-6: How many pounds of carbon monoxide would react with 125 pounds of iron (III) oxide?
You do it!You do it!
30
Calculations Based on Chemical Equations
CO lb 7.65CO g 454
CO lb 1
CO mol 1
CO g 28
OFe mol 1
CO mol 3
OFe g 7.159
OFe mol 1
OFe lb 1
OFe g 454OFe lb 125 = CO lb ?
3232
32
32
3232
YOU MUST BE PROFICIENT WITH THESE TYPES OF PROBLEMS!!!
Now go to your text and work the problems assigned!
31
Limiting Reactant Concept
Kitchen example of limiting reactant concept.1 packet of muffin mix + 2 eggs + 1 cup of milk
12 muffins
How many muffins can we make with the following amounts of mix, eggs, and milk?
32
Limiting Reactant Concept
Mix Packets Eggs Milk1 1 dozen 1 gallon
limiting reactant is the muffin mix2 1 dozen 1 gallon3 1 dozen 1 gallon4 1 dozen 1 gallon5 1 dozen 1 gallon6 1 dozen 1 gallon7 1 dozen 1 gallon
limiting reactant is the dozen eggs
33
Limiting Reactant Concept
Example 3-7: Suppose a box contains 87 bolts, 110 washers, and 99 nuts. How many sets, each consisting of one bolt, two washers, and one nut, can you construct from the contents of one box?
numbersmallest by the determined
sets 55 is make can number we maximum the
sets 99nut 1set 1nuts 99
sets 55 washers2set 1 washers110
sets 87bolt 1set 1bolts 87
34
Limiting Reactant Concept
Look at a chemical limiting reactant situation.
Zn + 2 HCl ZnCl2 + H2
35
Limiting Reactant Concept
Example 3-8: What is the maximum mass of sulfur dioxide that can be produced by the reaction of 95.6 g of carbon disulfide with 110. g of oxygen?
2222 SO 2 CO O 3 CS
36
Limiting Reactant Concept
Example 3-8: What is the maximum mass of sulfur dioxide that can be produced by the reaction of 95.6 g of carbon disulfide with 110. g of oxygen?
mol 2 mol 1 mol 3 mol 1
SO 2 CO O 3 CS 2222
37
Limiting Reactant Concept
Example 3-8: What is the maximum mass of sulfur dioxide that can be produced by the reaction of 95.6 g of carbon disulfide with 110. g of oxygen?
CS O CO 2 SO
1 mol 3 mol 1 mol 2 mol
76.2 g 3(32.0 g) 44.0 g 2(64.1 g)
2 2 2 2 3
38
Limiting Reactant Concept
Example 3-8: What is the maximum mass of sulfur dioxide that can be produced by the reaction of 95.6 g of carbon disulfide with 110. g of oxygen?
g 76.2
CS mol 1CS g 6.95 SO mol ?
SO 2 CO O 3 CS
222
2222
39
Limiting Reactant Concept
22
2
2
2
222
2222
SO g 161SO mol 1
SO g 1.64
CS mol 1
SO mol 2
g 76.2
CS mol 1CS g 6.95 SO mol ?
SO 2 CO O 3 CS
What do we do next?
You do it!You do it!
40
Limiting Reactant Concept
22
2
2
2
2
222
22
2
2
2222
2222
SO g 147SO mol 1
SO g 1.64
O mol 3
SO mol 2
O g 32.0
O mol 1O g 110SO mol ?
SO g 161SO mol 1
SO g 1.64
CS mol 1
SO mol 2
g 76.2
CS mol 1CS g 6.95 SO mol ?
SO 2 CO O 3 CS
Which is limiting reactant? Limiting reactant is O2. What is maximum mass of sulfur dioxide? Maximum mass is 147 g.
41
Percent Yields from Reactions
Theoretical yield is calculated by assuming that the reaction goes to completion.
– Determined from the limiting reactant calculation. Actual yield is the amount of a specified pure product
made in a given reaction.– In the laboratory, this is the amount of product that is formed in
your beaker, after it is purified and dried. Percent yield indicates how much of the product is
obtained from a reaction.
% yield = actual yield
theoretical yield100%
42
Percent Yields from Reactions
Example 3-9: A 10.0 g sample of ethanol, C2H5OH, was boiled with excess acetic acid, CH3COOH, to produce 14.8 g of ethyl acetate, CH3COOC2H5. What is the percent yield?
43
Percent Yields from Reactions
yield al theoretic theCalculate 1.
OH HCOOCCH OHHC + COOHCH 2523523
44
Percent Yields from Reactions
523
52
52352523
2523523
HCOOCCH g 1.19
OHHC g 0.46
HCOOCCH g 88.0 OHHC g 10.0= HCOOCCH g ?
yield al theoretic theCalculate 1.
OH HCOOCCH OHHC + COOHCH
45
Percent Yields from Reactions
yield.percent theCalculate .2
HCOOCCH g 1.19
OHHC g 0.46
HCOOCCH g 88.0 OHHC g 10.0= HCOOCCH g ?
yield al theoretic theCalculate 1.
OH HCOOCCH OHHC + COOHCH
523
52
52352523
2523523
46
Percent Yields from Reactions
%5.77%100HCOOCCH g 19.1
HCOOCCH g 14.8= yield %
yield.percent theCalculate .2
HCOOCCH g 1.19
OHHC g 0.46
HCOOCCH g 88.0 OHHC g 10.0= HCOOCCH g ?
yield al theoretic theCalculate 1.
OH HCOOCCH OHHC + COOHCH
523
523
523
52
52352523
2523523
47
Sequential Reactions
N O2 NH2HNO3
H2SO4
Sn
Conc. HCl
benzene nitrobenzene aniline
Example 3-10: Starting with 10.0 g of benzene (C6H6), calculate the theoretical yield of nitrobenzene (C6H5NO2) and of aniline (C6H5NH2).
48
Sequential Reactions
benzene g 0.78
benzene mol 1benzene g 10.0 = nenitrobenze g ?
49
Sequential Reactions
nenitrobenze g 8.15nenitrobenze mol 1
nenitrobenze g 0.123
benzene mol 1
nenitrobenze mol 1
benzene g 0.78
benzene mol 1benzene g 10.0 = nenitrobenze g ?
Next calculate the mass of aniline produced.
You do it!You do it!
50
Sequential Reactions
N O2 NH2HNO3
H2SO4
Sn
Conc. HCl
benzene nitrobenzene aniline
nenitrobenze g 123.0
nenitrobenze mol 1nenitrobenze g 15.8 = aniline g ?
51
Sequential Reactions
N O2 NH2HNO3
H2SO4
Sn
Conc. HCl
benzene nitrobenzene aniline
? g aniline = 15.8 g nitrobenzene1 mol nitrobenzene
123.0 g nitrobenzene
1 mol aniline
1 mol nitrobenzene
93.0 g aniline
1 mol aniline g aniline
11 9.
52
Sequential Reactions
If 6.7 g of aniline is prepared from 10.0 g of benzene, what is the percentage yield?
You do it!You do it!
%56%100aniline g 11.9
aniline g 6.7 = yield %
53
Concentration of Solutions
Solution is a mixture of two or more substances dissolved in another.– Solute is the substance present in the smaller amount.– Solvent is the substance present in the larger amount.– In aqueous solutions, the solvent is water.
The concentration of a solution defines the amount of solute dissolved in the solvent.
– The amount of sugar in sweet tea can be defined by its concentration. One common unit of concentration is:
w/w% symbol thehas solute of massby %
solvent of mass + solute of mass =solution of mass
%100solution of mass
solute of mass = solute of massby %
54
Concentration of Solutions
Example 3-12: Calculate the mass of 8.00% w/w NaOH solution that contains 32.0 g of NaOH.
nsol' g .400
NaOH g 8.00
solution g 100.0NaOH g 32.0 =solution g ?
55
Concentration of Solutions
Example 3-11: What mass of NaOH is required to prepare 250.0 g of solution that is 8.00% w/w NaOH?
NaOH g 0.20solution g 100.0
NaOH g 8.00solution g 0.250
56
Concentration of Solutions
Example 3-13: Calculate the mass of NaOH in 300.0 mL of an 8.00% w/w NaOH solution. Density is 1.09 g/mL.
You do it!You do it!
NaOH g 2.26nsol' g 100
NaOH g 8.00
nsol' mL 1
nsol' g 1.09nsol' mL 300.0 = NaOH g ?
57
Concentrations of Solutions
Example 3-14: What volume of 12.0% KOH contains 40.0 g of KOH? The density of the solution is 1.11 g/mL.
You do it!You do it!
58
Concentrations of Solutions
Example 3-14: What volume of 12.0% KOH contains 40.0 g of KOH? The density of the solution is 1.11 g/mL.
solution mL .300
solution g 1.11
solution mL 1
KOH g 12.0
solution g 100.0KOH g 40.0 =solution mL ?
59
Concentrations of Solutions
Second common unit of concentration:
mL
mmolL
molessolution of liters ofnumber
solute of moles ofnumber molarity
M
M
60
Concentrations of Solutions
Example 3-15: Calculate the molarity of a solution that contains 12.5 g of sulfuric acid in 1.75 L of solution.
You do it!You do it!
61
Concentrations of Solutions
Example 3-15: Calculate the molarity of a solution that contains 12.5 g of sulfuric acid in 1.75 L of solution.
42
424242
SOH g 98.1
SOH mol 1
nsol' L 75.1
SOH g 12.5
nsol' L
SOH mol ?
62
Concentrations of Solutions
Example 3-15: Calculate the molarity of a solution that contains 12.5 g of sulfuric acid in 1.75 L of solution.
42
42
42
424242
SOH 0728.0L
SOH mol 0728.0
SOH g 98.1
SOH mol 1
nsol' L 75.1
SOH g 12.5
nsol' L
SOH mol ?
M
63
Concentrations of Solutions
Example 3-16: Determine the mass of calcium nitrate required to prepare 3.50 L of 0.800 M Ca(NO3)2 .
You do it!You do it!
64
Concentrations of Solutions
Example 3-16: Determine the mass of calcium nitrate required to prepare 3.50 L of 0.800 M Ca(NO3)2 .
? g Ca(NO L 0.800 mol Ca(NO
L164 g Ca(NO
mol Ca(NO g Ca(NO
33
3
33
) .)
)
))
22
2
22
3 50
1459
65
Concentrations of Solutions
One of the reasons that molarity is commonly used is because:
M x L = moles solute
and
M x mL = mmol solute
66
Concentrations of Solutions
Example 3-17: The specific gravity of concentrated HCl is 1.185 and it is 36.31% w/w HCl. What is its molarity?
g/L 1185or g/mL 1.185=density
us tells1.185 =gravity specific
67
Concentrations of Solutions
Example 3-17: The specific gravity of concentrated HCl is 1.185 and it is 36.31% w/w HCl. What is its molarity?
nsol' g 100
HCl g 31.36
solution L
solution g 1185 = HCl/L mol ?
1185g/Lor g/mL 1.185=density
us tells1.185 =gravity specific
68
Concentrations of Solutions
Example 3-17: The specific gravity of concentrated HCl is 1.185 and it is 36.31% w/w HCl. What is its molarity?
HCl 11.80HCl g 36.46
HCl mol 1
nsol' g 100
HCl g 31.36
solution L
solution g 1185 = HCl/L mol ?
1185g/Lor g/mL 1.185=density
us tells1.185 =gravity specific
M
69
Dilution of Solutions
To dilute a solution, add solvent to a concentrated solution.– One method to make tea “less sweet.”– How fountain drinks are made from syrup.
The number of moles of solute in the two solutions remains constant.
The relationship M1V1 = M2V2 is appropriate for dilutions, but not for chemical reactions.
70
Dilution of Solutions
Common method to dilute a solution involves the use of volumetric flask, pipet, and suction bulb.
71
Dilution of Solutions
Example 3-18: If 10.0 mL of 12.0 M HCl is added to enough water to give 100. mL of solution, what is the concentration of the solution?
M
MM
MM
MM
20.1mL 100.0
mL 0.100.12
mL 100.0mL 0.10 0.12
VV
2
2
2211
72
Dilution of Solutions
Example 3-19: What volume of 18.0 M sulfuric acid is required to make 2.50 L of a 2.40 M sulfuric acid solution?
You do it!You do it!
73
Dilution of Solutions
Example 3-19: What volume of 18.0 M sulfuric acid is required to make 2.50 L of a 2.40 M sulfuric acid solution?
mL 333or L 0.333 18.0
2.40 L 2.50V
V V
V V
1
1
221
2211
M
M
M
M
MM
74
Using Solutions in Chemical Reactions
Combine the concepts of molarity and stoichiometry to determine the amounts of reactants and products involved in reactions in solution.
75
Using Solutions in Chemical Reactions
Example 3-20: What volume of 0.500 M BaCl2 is required to completely react with 4.32 g of Na2SO4?
NaCl 2 + BaSO BaCl + SONa 4242
76
Using Solutions in Chemical Reactions
Example 3-20: What volume of 0.500 M BaCl2 is required to completely react with 4.32 g of Na2SO4?
42
42422
4242
SONa g 142
SONa mol 1 SOgNa 4.32 BaCl L ?
NaCl 2 + BaSO BaCl + SONa
77
Using Solutions in Chemical Reactions
Example 3-20: What volume of 0.500 M BaCl2 is required to completely react with 4.32 g of Na2SO4?
L 0.0608 BaCl mol 0.500
BaCl L 1
SONa mol 1
BaCl mol 1
SONa g 142
SONa mol 1 SOgNa 4.32 BaCl L ?
NaCl 2 + BaSO BaCl + SONa
2
2
42
2
42
42422
4242
78
Using Solutions in Chemical Reactions
Example 3-21: (a)What volume of 0.200 M NaOH will react with 50.0 mL 0f 0.200 M aluminum nitrate, Al(NO3)3?
3 33 3Al NO 3 NaOH Al OH 3 NaNO
You do it!
79
Using Solutions in Chemical Reactions
Example 3-20: (a)What volume of 0.200 M NaOH will react with 50.0 mL 0f 0.200 M aluminum nitrate?
nsol' NaOH mL 150or L 0.150 NaOH mol 0.200
NaOH L 1
)Al(NO mol 1
NaOH mol 3
nsol' )Al(NO L 1
n sol' )Al(NO mol 0.200mL 1000
L 1nsol' )Al(NO mL 50.0 = NaOH mL ?
NaNO 3Al(OH)NaOH 3NOAl
3333
33
33
3333
80
Using Solutions in Chemical Reactions
(b)What mass of Al(OH)3 precipitates in (a)?
You do it!You do it!
81
Using Solutions in Chemical Reactions
(b) What mass of Al(OH)3 precipitates in (a)?
3
3
3
33
3
33
33
333
Al(OH) g 780.0
Al(OH) mol 1
Al(OH) g 0.78
)Al(NO mol 1
Al(OH) mol 1
nsol' )Al(NO L1
)Al(NO mol 0.200mL 1000
L1nsol' )Al(NO mL 50.0 Al(OH) g ?
82
Using Solutions in Chemical Reactions
Titrations are a method of determining the concentration of an unknown solutions from the known concentration of a solution and solution reaction stoichiometry.– Requires special lab glassware
Buret, pipet, and flasks
– Must have an an indicator also
83
Using Solutions in Chemical Reactions
Example 3-22: What is the molarity of a KOH solution if 38.7 mL of the KOH solution is required to react with 43.2 mL of 0.223 M HCl?
OH + KCl HCl + KOH 2
84
Using Solutions in Chemical Reactions
Example 3-22: What is the molarity of a KOH solution if 38.7 mL of the KOH solution is required to react with 43.2 mL of 0.223 M HCl?
HCl mmol 9.63 = HCl 0.223 mL 43.2
OH + KCl HCl + KOH 2
M
85
Using Solutions in Chemical Reactions
Example 3-22: What is the molarity of a KOH solution if 38.7 mL of the KOH solution is required to react with 43.2 mL of 0.223 M HCl?
KOH mmol 63.9HCl mmol 1
KOH mmol 1HCl mmol 9.63
HCl mmol 9.63 = HCl 0.223 mL 43.2
OH + KCl HCl + KOH 2
M
86
Using Solutions in Chemical Reactions
Example 3-22: What is the molarity of a KOH solution if 38.7 mL of the KOH solution is required to react with 43.2 mL of 0.223 M HCl?
KOH 249.0KOH mL 38.7
KOH mmol 9.63
KOH mmol 63.9HCl mmol 1
KOH mmol 1HCl mmol 9.63
HCl mmol 9.63 = HCl 0.223 mL 43.2
OH + KCl HCl + KOH 2
M
M
87
Using Solutions in Chemical Reactions
Example 3-23: What is the molarity of a barium hydroxide solution if 44.1 mL of 0.103 M HCl is required to react with 38.3 mL of the Ba(OH)2 solution?
HCl mmol 4.54 = HCl) HCl)(0.103 mL (44.1
OH 2 + BaCl HCl 2 + Ba(OH) 222
M
88
Using Solutions in Chemical Reactions
Example 3-23: What is the molarity of a barium hydroxide solution if 44.1 mL of 0.103 M HCl is required to react with 38.3 mL of the Ba(OH)2 solution?
HCl mmol 2
Ba(OH) mmol 1HCl mmol 54.4
HCl mmol 4.54 = HCl) HCl)(0.103 mL (44.1
OH 2 + BaCl HCl 2 + Ba(OH)
2
222
M
89
Using Solutions in Chemical Reactions
Example 3-23: What is the molarity of a barium hydroxide solution if 44.1 mL of 0.103 M HCl is required to react with 38.3 mL of the Ba(OH)2 solution?
2
2
222
Ba(OH) mmol 2.27 HCl mmol 2
Ba(OH) mmol 1HCl mmol 54.4
HCl mmol 4.54 = HCl) HCl)(0.103 mL (44.1
OH 2 + BaCl HCl 2 + Ba(OH)
M
90
Using Solutions in Chemical Reactions
Example 3-23: What is the molarity of a barium hydroxide solution if 44.1 mL of 0.103 M HCl is required to react with 38.3 mL of the Ba(OH)2 solution?
22
2
2
2
222
Ba(OH) 0593.0Ba(OH) mL 3.38
Ba(OH) mL 27.2
Ba(OH) mmol 2.27 HCl mmol 2
Ba(OH) mmol 1HCl mmol 54.4
HCl mmol 4.54 = HCl) HCl)(0.103 mL (44.1
OH 2 + BaCl HCl 2 + Ba(OH)
M
M
91
Synthesis Question
Nylon is made by the reaction of hexamethylene diamine
CH2CH2CH2
CH2CH2CH2NH2
NH2
C
OH
O CH2
CH2
CH2
CH2
C
OH
O
with adipic acid.
92
Synthesis Question
in a 1 to 1 mole ratio. The structure of nylon is:
CNH
O
CH2
CH2
CH2
CH2
CH2
CH2
C
O
CH2
CH2
CH2
NH ** n
where the value of n is typically 450,000. On a daily basis, a DuPont factory makes 1.5 million pounds of nylon. How many pounds of hexamethylene diamine and adipic acid must they have available in the plant each day?
93
Synthesis Question
moleculesnylon g/mol 10 1.02
450,000 g/mol] [226
000,450 ])162()142()221( 12) (12[ moleculenylon 1 of massMolar
8
units of #atoms Oatoms Natoms Hatoms C
94
Synthesis Question
g 106.81
lb
g 454lb) 10 (1.5 poundsmillion 1.5
moleculesnylon g/mol 10 1.02
450,000 g/mol] [226
000,450 ])162()142()221( 12) (12[ moleculenylon 1 of massMolar
8
6
8
units of #atoms Oatoms Natoms Hatoms C
95
Synthesis Question
nylon of mol 6.68
g 101.02
nylon mol 1 g 106.81 moleculesnylon of mol #
g 106.81
lb
g 454lb) 10 (1.5 poundsmillion 1.5
moleculesnylon g/mol 10 1.02
450,000 g/mol] [226
000,450 ])162()142()221( 12) (12[ moleculenylon 1 of massMolar
88
8
6
8
units of #atoms Oatoms Natoms Hatoms C
96
Synthesis Question
:requiresnylon of mol 6.68 make to
formed,nylon of moleper 450,000 diamine enehexamethyl of mole 1 plus
450,000 acid adipic of mole 1 usesreaction formation nylon theBecause
97
Synthesis Question
lb 1066.9g 454
lb 1g 104.39 g/mol 146450,000 6.68 - acid adipic
:requiresnylon of mol 6.68 make to
formed,nylon of moleper 450,000 diamine enehexamethyl of mole 1 plus
450,000 acid adipic of mole 1 usesreaction formation nylon theBecause
58
98
Synthesis Question
lb 1068.7g 454
lb 1g 1049.3 g/mol 116450,000 6.68 - diamine enehexamethyl
lb 1066.9g 454
lb 1g 104.39 g/mol 146450,000 6.68 - acid adipic
:requiresnylon of mol 6.68 make to
formed,nylon of moleper 450,000 diamine enehexamethyl of mole 1 plus
450,000 acid adipic of mole 1 usesreaction formation nylon theBecause
58
58
99
Group Activity
Manganese dioxide, potassium hydroxide and oxygen react in the following fashion:
OH 2 KMnO 4 O 3 + KOH 4 + MnO 4 2422 A mixture of 272.9 g of MnO2, 26.6 L of 0.250 M KOH, and 41.92 g of O2 is allowed to react as shown above. After the reaction is finished, 234.6 g of KMnO4 is separated from the reaction mixture. What is the per cent yield of this reaction?
100
End of Chapter 3