Chemistry Reference
In-Depth Information
Examples of Combustion Reactions
CH
4(g)
+ 2O
2(g)
CO
2(g)
+ 2H
2
O
(g)
2C
2
H
6(g)
+ 7O
2(g)
4CO
2(g)
+ 6H
2
O
(g)
combustion of methane
combustion of ethane
C
2
H
4(g)
+ 3O
2(g)
2CO
2(g)
+ 2H
2
O
(g)
2C
2
H
2(g)
+ 5O
2(g)
4CO
2(g)
+ 2H
2
O
(g)
combustion of ethene
combustion of ethyne
Lesson 6-2 Review
Identify the following chemical reactions as one of the five main types.
1.
2H
2
O
2
2H
2
O + O
2
2.
4Fe + 3O
2
2Fe
2
O
3
3.
Cl
2
+ 2NaBr
2NaCl + Br
2
4.
Zn + H
2
SO
4
ZnSO
4
+ H
2
5.
CH
4
+ O
2
CO
2
+ H
2
O
6.
Pb(NO
3
)
2
+ K
2
CrO
4
PbCrO
4
+ KNO
3
7.
2Ag + Cl
2
2AgCl
8.
6HCl + Fe
2
O
3
2FeCl
3
+ 3H
2
O
9.
MgO + CO
2
10. 2C
2
H
6
+ 7O
2
4CO
2
+ 6H
2
O
MgCO
3
Lesson 6-3: Ionic Equations
In Lesson 6-2, I mentioned that displacement reactions are a bit mis-
leading at times. Sometimes, a product that is shown on the product side of
the equation does not really appear in the physical chemical reaction. The
reason for this has to do with the solubility of ionic substances in water. If a
particular product is soluble, it will stay dissolved in the aqueous solution.
If a product is insoluble, it will appear as a solid precipitate in the test ves-
sel. It is important to know which products stay dissolved in the water, so
we can make proper identification of the precipitates that do form as the
result of the chemical reactions. Ionic equations are more realistic repre-
sentations of these reactions that take place in aqueous solution. Ionic equa-
tions show the individual ions that exist in solution. When we take an ionic
displacement reaction and remove the information that is misleading, we
produce a net ionic equation.
