Download 1 mole O 2

Essential Questions: What are the parts of a
chemical equation? What is a catalyst?
Word Equations:
Methane (g) + Oxygen (g) [Yield to
produce]Carbon dioxide (g) + Water (l)
Reactants  Product
Phases:
Gas (g) Liquid (1) Solid (s)
Other symbols are used in equations.
Catalyst:
• Substance that speeds up a rxn.
• Written above the
• Not a reactant or a product
Ex. H202(g) H20(1) + 02(g)
Essential Question: How do you balance a
chemical equation?
Balancing Equations:
1. Determine correct formulas for
reactants/products.
2. Balance each compound using oxidation
numbers.
3. Balance each compound using coefficients.
4. Make sure coefficients are in the lowest
ratio.
Exs:
A. Solid zinc reacts with a water solution of
hydrogen sulfate to produce hydrogen
gas, a water solution of zinc sulfate, and
heat.
Zinc(sy + hydrogen sulfate (g) hydrogen (g)
+ zinc sulfate (g)
Zn(s) + H2SO4 (g) H2 (g) + Zn+1SO4
therefore is balanced.
B. Calcium hydroxide + Sulfuric acid
Calcium sulfate + Water.
 Balance each compound using
coefficients.
Calcium hydroxide + Sulfuric acidCalcium
sulfate + water
Ca (OH)2 + H2S04Ca (SO4) + H2O
Using Rule #4:
Inspect the three equations below. Are they
balanced?
2 CH4 + 4O22CO2 + 4H2O
6 CH4 + 12O26CO2 + 12H2O
1/2 CH4 + O21/2 CO2 + H2O
The first two are balanced but are they in
the smallest whole-numbers ratio? (Rule
4)
*NO, it should be CH4 + 2O2CO2 + 2H2O
Essential Questions: What are the four types of
reactions? What is general formula for each
type? What is the relationship of Table J to
writing equations?
Types of Reactions:
 Combination (synthesis)
 Decomposition
 Single replacement
 Double replacement
Synthesis:
• Two or more reactants combine to form a
single product
• General Formula:
A +BAB
H +Cl HCl
Na + Cl NaCl
Decomposition:
• Reverse of synthesis
• A single compound is
broken down (decomposed
into two or more simpler
substances)
• General Formula:
ABA + B
Exs:
2 H2O2(1)2 H2O(1) + O2
2 NH3(g)N2(g) + 3 H2(g)
Single Replacement
Single replacement:
 Rxn, in which one element replaces
another element in a compound.
 General formula:
A + BCAC + B
** Use table J to determine if rxn will occur.
Exs:
Zn (s) + CuS04 ZnS04(g) + Cu(s)
Mg + 2 HClH2 + MgCl2
Table J
** Use table J to determine if rxn will
occur.
• A reactive metal will replace any other
metal below it.
Exs:
a. Zn + Cu(NO3)2Cu + ZnNO3)2
b. Cu + Zn(NO3)2no rxn
c. F2 + NaCl  Cl2 + NaF
d. C12 + NaFno rxn
Double Replacement:
• Chemical change involving an exchange of
positive ions between two compounds.
(Between two ionic compounds)
• Generally occur in an aqueous solution.
• Often produces a gas, precipitate or a molecular
compound. (H2O)
• General formula:
AB + CDAD + CB
Exs.
Ag(NO3)(aq)+ NaCl
(aq)NaNO 3(aq)+
AgCl(s)
Ba(N03)2(aq)+ Na2SO4(aq)BaSO4(s)+ 2
Na(NO3) (aq)
Essential Question: What are the three types of
situation in which a double replacement
reaction will occur?
Three situations in which a double
replacement will occur:
1 . One product is a solid (precipitate)
 Table F
AgNO3(aq) + NaCl (aq)AgCl(s) + NaNO3(aq)
 NaCl is a solid (insoluble)
 NaNO3 is a soluble therefore, rxn occurs.
2. A rxn in which a gas is produced
NaS(g) + 2 HCl(aq)H2S(g) + 2 NaCl(aq)
3. A rxn in which a molecular substance
is formed(H2O)
NaOH (aq) + HCl (aq)H2O(l) + NaOH (aq)
Essential Questions: What is a mole?
What is Avogadro’s number?
Mole:
 Is a specific number of particles
 1 mole of any substance =
6.02 x1023particles (Avogadro’s number)
**A mole of any substance contains Avogadro's
number of particles (6.02 x l023) **




1 mole of
1 mole of
1 mole of
1 mole of
Ag = 6.02 x1023 atoms of Ag
CO2 = 6.02 x1023 molecules of CO2
Ca ions = 6.02 x1023 ions
N2 = 6.02 xl023 molecules of N2
Types of Mole Problems:
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Atoms -Moles
Moles-Atoms
Grams-Moles
Moles-Grams
Mole-Mole (equations)
Mass—Mass (equations)
Mass-Volume (equations)
Volume-Volume (equations)
# of Particles (equations)
1. Atoms-Mole:
Ex. Magnesium is a light metal used in the manufacture of
aircraft, automobile wheels, tools, and garden furniture.
How many moles of magnesium are in 1.25x10 23 atoms of
magnesium?
a. List knows/unknowns:
Known:
Unknown:
1 mole Mg = 6.02x1023 atoms Mg
# of moles of Mg
# of atoms Mg = 1.25 x l023 atoms
atoms Mgmoles Mg
b. Solve problem:
1.25 xl 023 atoms Mg x 1 mole Mg
6.02xlO23atomsMg
=1.25xl023x lmoleMg
6.02x1023
=2.08 x lO-1 mole Mg =.208 mole Mg
B. How many moles are 2.08 x 1023 atoms
of silicon?
a. List known/unknown:
Known:
Unknown:
1 mole Si =6.02xl023 atoms moles of Si
2.80x1023= # of atoms
Atoms Si  mole Si
b. Solve
2.80xl023 atoms Si x 1 mole Si
6.02x1023atoms Si
=4.65 mole Si
2. MolesAtoms
:
How many atoms are in a mole of CO2?
a. List known/unknown
Known :
Unknown:
1 mole CO2=6.02xl023 molecules
#of atoms of CO2
CO2= 1 atom C
2 atoms O
Therefore 3 atoms in CO2
b. Solve:
1 mole CO2 x 3(6.02x10 23 atoms CO2)
1 Mole CO2
=18.06xlO23atoms
B. Propane is a gas used for cooking and heat. How
many atoms are in 2.12 moles of propane (C3H8)?
a. List Known/Unknown
Known:
Unknown:
2.12 moles of C3H8
atoms of C3H8
1 mole of C3H8 = 6.02x1023 molecules C3H8
(3C and 8H)
2.12moles C3H8 x 11(6.02 x 1023)
1mole C3H8
=1.4039 x l025 atoms C3H8
=1.40 x l025atoms C3H8
3. Grams Moles:
Formula Mass- the sum of masses of all the
atoms in a given formula
Find the formula mass of O2
A. O2 = 2 atoms x 16amu=32 amu(formula mass)
*1 mole of any substance = formula mass
therefore, 1 mole of O2= 32g/mole
B. Find the formula mass of CuSO4
Cu=l atom x 63.55amu=63.55amu
S= 1 atom x 32.07amu= 32.07 amu
O= 4 atom x 16amu = 64.00 amu
159.62 amu
Gram Formula Mass- The formula
mass expressed in grams.
** 1 mole of any substance=
Formula mass
Ex. How many moles are equivalent to 4.75g
NaOH?
a. Known
Unknown
4.75g NaOH
moles of
NaOH
b. Calculate GFM (gram formula mass) of
NaOH
Na=23amu
O=16 amu
H=l amu
40amu= 40g/mole NaOH
C. Solve: 4.75g NaOH x 1 mole NaOH
40gNaOH
=0.119 moles of NaOH
4. MolesGrams:
Ex. How many grams are present in 40.5 moles of H2SO4?
A. Known
Unknown
40.5 moles H2SO4
# grams ofH2SO4
B Calculate GFM:
H= 2amu x 2 =4
S= 32amu
O= 16amu x 4 = 64
=98 amu= 98 g/mole
Solve:
40.5 mole H2SO4 x 98gH2SO4
1 mole H2SO4
=3970g H2SO4
5. MoleMole
a. In the equation N2 + 3H22NH3, how many
moles of N2 are needed to produce 5.0 moles of
NH3?
Moles NH3 moles of N2
5.0 mole NH3 x 1 mole N2
2 Moles NH3
= 2.5 mole N2
b. In the equation 2NO + O2  2 NO2, How many
moles of O2 are needed to produce 3.5 moles of
NO2?
Moles of NO2 Moles of O2
3.5 moles of NO2 x 1 mole O2
2 moles NO2
= 1.75 mole O2
Mole Mass:
a. In the equation:
4Al +3O22 A12O3, how many grams of
aluminum will combine with 1.50 moles of
oxygen?
Mole Grams
1.50 mole O2 x 4 mole Al x 27g Al
3 mole O2 1 mole Al
=54 g Al
b. Based on the previous equation, how
many moles of O2 are needed to produce
51.0 g of Al2O3?
GramsMoles
51 .O g A12O3 x 1 mole Al2O3 x 3 mole O2
102g Al2O3
2 moleAl2O3
=.75 mole O2
8. MassMass:
a. In the equation,
CH4 + 2 O2 2 H2O, how many grams of CO2 are
formed when 8.0g of CH4 reacts with an excess of
CO2?
8.0g CH4 x 1 mole CH4 x 1 mole CO2 x 44 g CO
16gCH4
1 mole CH4 1 mole CO2
= 22g C02
b. In the equation 2 H2O22H2O+ O2, how
many grams of 02 will be formed from the
decomposition of 17.0g of H2O2?
17.0g H2O2 x 1 mole H2O2 x 1 mole O2 x 32O2
34g H2O2
2 mole H2O2 1 mole O2
=8.0g O2
9. MassVolume:
**1 mole of any substance = 22.4L(STP)
a. In the equation:
2 CO (g) + O2 (g)  2 CO2 (g), how many liters of
CO2, at STP are produced by the reaction of
64.0g of O2 (g)
64g O2 x 1 mole O2x 2 mole CO2_ x 22.4L CO2
32g O2
1 mole O2
1 mole CO2
= 89.6 L CO2
b. In the equation:
2 CO(g) + O2 (g) 2 CO2 (g) How many liters of O2
(g) at STP are able to react with 28.0g of CO(g)?
28.0gCO x 1 mole CO2 x 1 mole O2x 22.4L O2
28gCO
2 mole CO
1 moleO2
= 11.2 L O2
10. VolumeVolume:
In the equation 4 NH3 (g) + 5 O2(g)4NO(g) + 6
H20(l). How many liters of NH3 (g) at STP are
needed to react with 200 L of O2 (g) at STP?
2.0 L O2 x 1 mole O2 x 4 mole NH3 x 22.4 L NH3
22.4 L O2
5 mole O2 1 mole NH3
=160L NH3
b. In the equation:
4 NH3 (g) + 5 O2 (g) 4 NO(g) + 6 H2O(l)
How many liters of NH3 (g) at STP are
needed to produce 1000 L of NO(g) at
STP?
1OOL NO x l mole NO x 4 mole NH3 x 22.4LNH3
22.4L NO 4 mole NO 1 mole NH3
= 1,OOOL NH3
Number of particles :
a. In the equation:
2 C2H6+ 7 O2  4 CO2 + 6 H2O, how many
molecules of C2H6 are needed to produce
27.Og of H2O?
27.0g H2O x 1 mole H2O x 2 mole C2H6 x
18gH2O
6moleH2O
6.02xl023 mole
1 mole C2H6
= 3.01xl023 molecules of C2H6
b. in the equation 2 C2H6 + 7 O2 4 CO2 +
6 H2O, how many molecules of CO2 are
produced when 3.5 moles of O2 react?
3.5 mole O2 x 4 mole CO2 x 6.02x1023 molecules
of CO2
7 mole O2
1 mole CO2
=12.04x 1023 molecules of C02
=1.204x 1024 molecules of C02
Limiting Reactant (regent)- a reactant
that limits the amount of production of
product formed in a reaction.