This features the types of chemical reactions: Combustion, Neutralization, Precipitation and RedOx Reactions.
There are sample in each of the type of reaction that can help the learners understand more about each type.
2. OVERVIEW
CHEMICAL REACTIONS do not limit only from the 4 Basic
Types.
The actual phenomenon of the process involves special
cases of Chemical Change such as mentioned earlier.
Today’s lesson will focus to some Chemical Reactions that
are relevant and can explain our common practices at
home, school, etc.
4. Combustion Reactions
A Combustion Reaction is a major class of chemical reactions,
commonly referred to as "burning".
Combustion usually occurs when a hydrocarbon and some
organic compounds reacts with oxygen to produce carbon
dioxide and water.
In the more general sense, combustion involves a reaction
between any combustible material and an oxidizer to form an
oxidized product.
7. Combustion Reactions
Write the products of the and balance the chemical equations:
• C3H6 + O2 ՜
∆
• C10H22 + O2 ՜
∆
• C6H6 + O2 ՜
∆
• C2H5OH + O2 ՜
∆
• C9H16 + O2 ՜
∆
8. Acid – Base Reactions
Ammonia Hydrochloric acid
9. Arrhenius Definition of Acids and Bases
✓derived from the Theory of Electrolytes
Proposed by Svante Arrhenius in the late 1800
✓The Theory of Electrolytes states that
compounds dissolved in water ultimately form
ions.
✓An acid is a substance that, when dissolved in
water, increases of Hydrogen ions, H+ in solution.
✓A base is a substance that, when dissolved in
water, increases hydroxide ions, OH—1, in the
solution.
✓The reaction of an acid and a base produce salt
and water.
10. BrØnsted – Lowry Definition of Acids and Bases
✓An Acid is a proton donor.
✓A base is a proton acceptor.
✓An acid – base reaction involves the transfer of a proton from an acid to a base
forming a new acid and a new base. The reaction is written as an equilibrium
reaction, and the equilibrium favors the weaker acid and base.
12. BrØnsted – Lowry Definition of Acids and Bases
✓HCl is a strong electrolyte because it ionizes completely forming Hydronium ion in
aqueous solution; it thus classified as a strong acid.
✓Acetic acid is a weak electrolyte but ionized to a small extent in water and therefore is
a weak acid.
13. BrØnsted – Lowry Definition of Acids and Bases
MULTIPROTIC ACIDS
14. BrØnsted – Lowry Definition of Acids and Bases
Neutralization Reaction
Acids and bases in aqueous solution react to produce salt and water.
The word “salt” comes to a language of chemistry to describe any ionic compound
whose cation comes from a base and an anion comes from an acid.
15. YOUR TURN!
Predict the Products of the following and balance the
Chemical Equation:
1. Ammonium hydroxide and Hydrobromic acid
2. Aluminum hydroxide and Hydrosulfuric acid
3. Barium hydroxide and Boric acid
4. Hydrocyanic acid and Magnesium hydroxide
5. Nitric acid and Manganese (II) hydroxide
17. Chemical Reactions in Aqueous Solution
Aqueous Solution is a homogenous mixture wherein the
solvent is Water.
A water molecule is electrically positive on one
side of its molecule (the H atoms) and electrically
negative on the other (the O atom).
18. Chemical Reactions in Aqueous Solution
Dissolving Copper (II) sulfate Introducing Copper (II) sulfate to Ammonium
hydroxide producing Tetraamminediaquacopper
dihydroxide [Cu(NH3)4(H2O)2](OH)2
19. Chemical Reactions in Aqueous Solution
Compounds whose aqueous solution conduct electricity
are called electrolytes. All ionic compounds that are
soluble in water are considered electrolytes.
20. Chemical Reactions in Aqueous Solution
Electrolysis is a method that uses electrical energy so that
Chemical Reaction will occur.
Electrolysis of Copper (II) sulfate
21. Chemical Reactions in Aqueous Solution
Many Ionic compounds dissolve completely in water, but
some dissolve only in small extent, and still others are
essentially insoluble.
22. Chemical Reactions in Aqueous Solution
With the help of the solubility guidelines, it is easy to predict
whether the compounds are water – soluble or not. But there are
exceptions.
23. Chemical Reactions in Aqueous Solution
A Precipitation Reaction produces a water – insoluble solid
product, known as Precipitate.
The reactants in such reactions are generally water – soluble
ionic compounds.
When dissolved in water, they dissociate to give appropriate
cations and anions.
If the cation from one compound can form an insoluble
compound with the anion from the other compound in the
solution, precipitation occurs.
24. Chemical Reactions in Aqueous Solution
Example of Precipitation Reaction:
AgNO3(aq) + KCl(aq) ⟶ AgCl(s) + KNO3(aq)
Balance the Equation: AgNO3(aq) + KCl(aq) ⟶ AgCl(s) + KNO3(aq)
Complete Ionic Equation:
Ag+1
(aq)+NO3
—1
(aq)+ K+1
(aq)+Cl—1
(aq) ⟶ AgCl(s) + K+1
(aq) +NO3
—1
(aq)
Ag+1
(aq)+NO3
—1
(aq)+ K+1
(aq)+Cl—1
(aq) ⟶ AgCl(s) + K+1
(aq) +NO3
—1
(aq)
Net Ionic Equation:
Ag+1
(aq)+Cl—1
(aq) ⟶ AgCl(s)
Potassium and Nitrate ions are called SPECTATOR IONS because they do not participate in the NIE; they only look on from the sidelines.
26. Chemical Reactions in Aqueous Solution
Let’s have more!
• Solutions of Aluminum chloride and Sodium phosphate
• Solutions of Iron(III) chloride and Potassium hydroxide
• Solutions of Lead(II) nitrate and Potassium chloride
Your Turn!
1. Solutions of Barium chloride and Sodium sulfate
2. Solutions of Potassium carbonate and Sodium nitrate
3. Solutions of Barium hydroxide and Nickel(II) chlorate
28. Oxidation – Reduction Reaction (REDOX)
Oxidation – Reduction Reaction (or
REDOX) is a reaction involving the
transfer of one or more electron(s)
from one species to another.
Oxidation – when substances lose
electron(s). The substance is then
considered as a reducing agent.
Reduction – when substances gain
electron(s). The substance is an
oxidizing agent.
29. Oxidation – Reduction Reaction (REDOX)
How can you tell if REDOX occurs?
It can be determined by looking for a change of the oxidation
number in the course of a chemical reaction.
Oxidation Number of an atom in a molecule or ion is defined as
the charge of an atom.
30. Oxidation – Reduction Reaction (REDOX)
Oxidation number appears to have as determined by the
following guidelines:
1) Each atom in a pure element has an oxidation number of zero.
Ex. Cu + FeCl3 ⟶ CuCl2 + Fe
0 0
31. Oxidation – Reduction Reaction (REDOX)
2) For monatomic ions, the oxidation number is equal to the
charge of the ion.
Ex. 3Cu + 2FeCl3 ⟶ 3CuCl2 + 2Fe
3) When combined with other element, fluorine has always an
oxidation number of – 1.
Ex. 2Na + F2 ⟶ 2NaF
+3 -1 +2 -1
0 0
0 0 +1 -1
32. Oxidation – Reduction Reaction (REDOX)
4a) The oxidation number of O is – 2 in many compounds.
Ex. 2Mg + O2 ⟶ 2MgO
4b) When oxygen combines with fluorine, it is +2.
Ex. O2 + 2F2 ⟶ 2OF2
4c) Peroxides (O2
-2) and Superoxides (O2
—1) have oxidation
states of – 1 and – ½, respectively.
+2 -2
0 0
0 0 +2-1
33. Oxidation – Reduction Reaction (REDOX)
5) Cl, Br and I have oxidation numbers equal to – 1, except when
combined with O and F, which will become +1.
6) The oxidation number of Hydrogen is +1 in most compounds
but when formed compounds with metals, it is -1.
7) The algebraic sum of the oxidation numbers for the atoms in a
neutral compound must be zero; in a polyatomic ion, the sum
must be equal to the ion charge.
34. Oxidation – Reduction Reaction (REDOX)
Determine which element has oxidized and which
has reduced of the following Chemical Equations.
1. Mg + F2 ⇾ MgF2
2. 2Ag2O ⇾ 4Ag + O2
3. Cu + 2AgNO3 ⇾ Cu(NO3)2 + 2Ag
4. CH4 + 2O2 ⇾ CO2 +2H2O
5. 2NaHCO3 ⇾ Na2O + 2CO2 + H2O
6. NaOH + HCl ⇾ NaCl + H2O
35. Answers to Items 1and 3:
0 0 +2 -1
1. Mg + F2 ⇾ MgF2
Therefore, Magnesium is OXIDIZED and also the REDUCING AGENT
because it lost 2 electrons. Fluorine is REDUCED and also the
OXIDIZING AGENT because it gains 1 electron. The type of RedOx
Reaction is SYNTHESIS.
0 +1 +5 -2 +2 +5 -2 0
3. Cu + 2Ag N O3 ⇾ Cu(NO3)2 + 2Ag
Oxidized/ Reducing agent = Cu; Reduced/Oxidizing agent:
Ag; Type of RedOx Reaction: Single Displacement
