Reaction Types 6 Combustion

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Redox and Combustion
My new book on GOLF will give
the reader valuable playing tips
and insider information I've
gained through my years of
lessons, struggles and
experiments.
Here are just a few of the
chapter titles:
Chapter 1 - How to Properly Line Up
Your Fourth Putt..
Chapter 4 - How to Get More Distance
off the Shank.
Redox and Combustion:
At the conclusion of our time together,
you should be able to:
1. Identify a basic combustion reaction
2. Show the change in oxidation numbers for
a combustion reaction
5. Combustion Reactions
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Combustion reactions occur
when a hydrocarbon reacts
with oxygen gas.
This is also called burning!!!
In order to burn something
you need the 3 things in
the “fire triangle”:
1) A Fuel (hydrocarbon)
2) Oxygen to burn it with
3) Something to ignite the
reaction (spark)
Combustion Reactions
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•
•
In general:
CxHy + O2  CO2 + H2O
Products in combustion are
ALWAYS carbon dioxide and
water. (although incomplete
burning does cause some byproducts like carbon monoxide)
Combustion is used to heat
homes and run automobiles
(octane, as in gasoline, is C8H18)
Combustion Reactions
•
•
•
In general:
CxHy + O2  CO2 + H2O
They are always exothermic
(they give off heat)
What Do You Get When You Cross a
Snowman With a Vampire?

Frostbite.
Combustion Reactions
Edgar Allen Poe’s
drooping eyes and
mouth are potential
signs of CO poisoning.
Combustion of Butane:
Predict the products and balance the
reaction:
2 C4H10 + 13 O2  8 CO2 + 10 H2O
Combustion of Propanol
Predict the products and balance the
reaction:
2 C3H7OH + 9 O2  6 CO2 + 8 H2O
Combustion of Methane and Redox
CH4 + 2 O2  1 CO2 + 2 H2O
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Show the change in oxidation numbers:
C-4  C+4
Each carbon loses 8 electrons – oxidation,
reducing agent
O  O2Each oxygen gains 2 electrons – reduction,
oxidizing agent
This Does Seem a Little Weird!!???
Redox and Combustion:
Let’s see if you can:
1. Identify a basic combustion reaction
2. Show the change in oxidation numbers for
a combustion reaction
Practice
Predict the products and balance the reaction of
hexene burning in air:
C6H12 + O2 
C6H12 + 9 O2  6 CO2 + 6 H2O
•
Show the change in oxidation numbers:
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C-2  C+4
•
Each carbon loses 6 electrons – oxidation,
reducing agent
•
O  O2•
Each oxygen gains 2 electrons – reduction,
oxidizing agent
I don’t feel so stupid now…
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