4/7/2014
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Today:
◦ Types of Chemical Reactions:
 Redox Reactions:
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Combustions
Single Replacement Reactions
Decompositions
Synthesis Reactions
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iClicker Participation Question:
Acid-Base Titrations
Consider the reaction of KOH with H3PO4.
What volume of 5 M KOH(aq) would be needed to fully react
with 50 mL of 1 M H3PO4?
A. 10 mL
B. 30 mL
C. 50 mL
D. 150 mL
E. 250 mL
Double Replacements:
Redox Reactions:
Combustions
Single Replacements
Decompositions
Types of Reactions
Reactions can be grouped
into general categories.
Each category follows a
pattern that can be used
to predict the possible
products & outcomes of
the chemical reaction in
question.
Synthesis
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SINGLE Replacement Reactions
Single Replacement: a reaction where one type of element is
replaced with another.
This most often occurs when an ionic compound reacts with
a substance composed of a single element.
Single replacement reactions are a type of of REDOX
reaction (involving an exchange of electrons)
Batteries make use of Redox reactions: Write the balanced equation
for Zinc metal reacting with copper (II) sulfate to produce zinc (II) sulfate
and copper metal.
Galvanized Steel
Iron metal corrodes in the presences of oxygen and water to produce rust
(Fe2O3), which compromises the strength of the metal. Galvanized steel
uses a barrier of zinc or magnesium metal to protect the iron from
corrosion.
Write the balanced equation for magnesium
metal reacting with Iron (III) Oxide (aka “rust”)
to produce Iron metal & magnesium oxide.
Single Replacement Reactions
Not all possible single replacement reactions will
occur.
It depends on the reactivity of the element that is
trying to displace the element in the compound.
In order for a single replacement reaction to take place,
the free element that is replacing the element in the
compound must be higher in the activity series.
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Metals
MOST Reactive
Lithium (Li)
Potassium (K)
Barium (Ba)
Calcium (Ca)
Sodium (Na)
Magnesium (Mg)
Aluminum (Al)
Manganese (Mn  Mn2+)
Zinc (Zn)
Chromium (Cr  Cr3+)
Iron (Fe  Fe2+)
Cadmium (Cd)
Cobalt (Co  Co2+)
Nickel (Ni  Ni2+)
Tin (Sn  Sn2+)
Lead (Pb  Pb2+)
Hydrogen (H2)
Copper (Cu  Cu2+)
Silver (Ag)
Mercury (Hg  Hg+)
Platinum (Pt  Pt2+)
Gold (Au  Au3+)
LEAST Reactive
Nonmetals
Reactivity
Series
MOST Reactive
Fluorine (F2)
Oxygen (O2)
Chlorine (Cl2)
Bromine (Br2)
Iodine (I2)
LEAST Reactive
Note:
All reactivities are for the
most common ion formed.
In the cases of elements
that can form more than
one ion, the ion indicated
is the most common ion.
In the course of history, the discovery of single reactions has repeatedly
revolutionized human civilizations. The start of the Iron Age around 1300 B.C.
marked the moment we learned to transform brittle iron ores to iron metal.
This affected everything from how we grew food to how we waged wars.
Write the balanced chemical equation describing
iron (III) oxide reacting with carbon atoms to form
iron metal and carbon dioxide.
• How much iron metal could be produced from 100.0 grams of Fe2O3
& 30. grams of Carbon? What if only 10.3 grams of iron metal were
obtained? What would be the percent yield?
Combustions: Reactions with Oxygen (O2)

Combustion often occurs with hydrocarbons (CxHy) to produce
CO2 & H2O:
Balance Carbon first, Hydrogen second, and Oxygen last.

Other substances can also combust (“burn”) in oxygen.
◦ Write the combustion of Iron metal to product Iron (III) Oxide (aka “rust”)
◦ Write the combustion of Phosphorus (as P4) to form P4O10
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iClicker Participation Question:
Combustion of Gasoline
How many oxygen molecules (O2) are needed to
completely react with one molecule of C7H16
(a component of gasoline) to form
A. 7
carbon dioxide and water?
B. 8
C. 11
D. 14
E. 22
Decomposition: From One to Many

A single substance breaks into multiple simpler substances
◦ Some decompositions are SPONTANEOUS.
 Example: Hydrogen peroxide decomposes to oxygen gas and water
 Example: Carbonic acid (H2CO3) decomposes
to carbon dioxide gas & water
◦ Others decompositions require heat, light
or electrical current to occur.
 Example: Water can be forced to break into its
component elements through electrolysis
(decomposition from electricity)
Thermal Decomposition:
Breaking a substance down with thermal energy
Write the balanced equation for the decomposition of mercury (II)
oxide to produce mercury metal & oxygen gas
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SYNTHESIS
Simple substances combine to form more complex compounds.
Example: Tungesten (IV) carbide can be made by heating Tungsten
metal with Carbon to 1400 oC. Write the balanced chemical equation for
this process.
Example: Write the balanced equation for forming Chlorine Trifluoride
from Chlorine & Fluorine gas.
In an industrial accident, a spill of 900 kg of chlorine trifluoride BURNED
through 12 inches of concrete & almost 3 feet of gravel beneath!
Consider the reaction of 20.0 mL of a sulfuric acid solution
with a 0.127 M solution of sodium hydroxide:
H2SO4(aq) + 2 NaOH(aq) → Na2SO4(aq) + 2 HOH(l)
20.0 mL
Concentration = ?
32.66 mL
0.127 M
If 32.66 mL of NaOH is required to
fully react with the H2SO4 solution,
what is the concentration (in mol/L) of
the original H2SO4 solution?
Concentration =
𝒎𝒐𝒍𝒆𝒔 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒆
𝒗𝒐𝒍𝒖𝒎𝒆 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏 (𝑳)
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