Download What are the general types of reactions?

S-133
• Write the formula for
– Palladium (IV) Oxide
– Calcium Fluoride
– Cadmium (II) Nitride
Write the name for
- Al2S3
- Rb3P
- CrO3
Unit 7 Chemical Reaction
SPS2. Students will explore the nature of matter, its classifications, and its system for naming types of matter.
d.
Demonstrate the Law of Conservation of Matter in a chemical reaction.
e.
Apply the Law of Conservation of Matter by balancing the following types of chemical equations;
-
Synthesis
Decomposition
Single Replacement
Double Replacement
7.1 Describing Reactions
What is the law of conservation of mass?
Why must chemical equations be balanced?
Why do chemists use the mole?
How can you calculate the mass of a reactant or product in a
chemical reaction?
7.1 Describing Reactions
What is the law of conservation of mass?
• Chemical Equations
– Reactants – the substances that are present before
a reaction
– Products – the substances present after a reaction
is complete
– Always given in the form
Reactants  Products
– Example:Carbon + Oxygen  Carbon Dioxide
– Or
C + O2  CO2
7.1 Describing Reactions
What is the law of conservation of mass?
• Writing Equations - Practice
– Copper and Oxygen make Copper (II) Oxide
– Magnesium and Hydrogen Chloride make
Hydrogen and Magnesium Chloride
– Ethylene (C2H4) burns with Oxygen to produce
Carbon Dioxide and Water.
– Hydrogen and Chlorine combine to make
Hydrogen Chloride
7.1 Describing Reactions
What is the law of conservation of mass?
• Conservation of Mass
– Mass is not created or destroyed in a chemical
reaction
– For practical purposes
• Same types of atoms before and after a reaction
• Same number of each type of atom before and after
– Equations must show this
– They are called balanced equations
S-134
• Write the formula for
– Dinitrogen Trioxide
– Copper (II) oxide
– Dinitrogen Pentaoxide
Write the name for
- CCl4
- CrBr3
- Mo2O5
S-135
• Write the equation for a reaction of
hydrogen sulfide with aluminum oxide to
make aluminum sulfide and water.
7.1 Describing Reactions
Why must chemical equations be balanced?
• Balancing Equations
– If an equation does not have the same elements
on both sides, it is a false equation
• Can not actually occur
– Coefficient – a number placed in front of a
substance in a chemical equation
• Used to balance equations
7.1 Describing Reactions
Why must chemical equations be balanced?
• Balancing Equations - Steps
– First write out the equation
• Hydrogen and Oxygen make water becomes
• H2 + O2  H2O
– List the elements on each side
H-2
O-2

H-2
O-1
– Add substances until both sides are equal
7.1 Describing Reactions
Why must chemical equations be balanced?
• Balancing Equations - Practice
– Copper and Oxygen make Copper (II) Oxide
– Magnesium and Hydrogen Chloride make
Hydrogen and Magnesium Chloride
– Ethylene (C2H4) burns with Oxygen to produce
Carbon Dioxide and Water.
S-137
• Balance the following equations
H2SO4 + Al(OH)3  Al2(SO4)3 + H2O
7.1 Describing Reactions
Why do chemists use the mole?
• Counting With Moles
18
Ar
39.95
– A unit of measurement
Argon
23
– Equals 6.02 x 10 of anything
– Used only to count atoms, molecules, formula
unit
– One mole of an element is equal to its atomic
mass converted to grams (put a g beside the
number)
7.1 Describing Reactions
How can you calculate the mass of a reactant or product in a reaction?
• Molar Mass
– For an element equal to its atomic mass
– For a compound
• For each element – multiply the mass x the number of
that element in the compound
• Add the total
7.1 Describing Reactions
How can you calculate the mass of a reactant or product in a reaction?
• Molar Mass-Example
– C 2 H4
– Carbon
– Hydrogen
–
12.01g x 2 = 24.02g
1.01g x 4 = 4.04g
Total 28.06
7.1 Describing Reactions
How can you calculate the mass of a reactant or product in a reaction?
• Molar Mass-Example
– Pb(OH)4
S-137
• What is the molar mass of
Al2(SO4)3
7.2 Types of Reactions
What are the general types of chemical
reactions?
Types of Reactions
What are the general types of reactions?
•
Classifying Reactions
–
–
Describe how reactants interact to form
products
Help to predict the products of reactions
Types of Reactions
What are the general types of reactions?
•
Synthesis
–
–
–
–
Two or more substances react to form a single
substance
Pattern
A + B  AB
Always has one product
Examples
•
•
2Na + Cl2  2NaCl
2H2 + O2  2H2O
Types of Reactions
What are the general types of reactions?
•
Decomposition
–
–
–
–
One substance breaks apart into two or more
products
Pattern
AB  A + B
Always has one reactant
Examples
•
•
CaCO3  CaO + CO2
2H2O  2H2 + O2
Types of Reactions
What are the general types of reactions?
•
Single Replacement (Displacement)
–
–
–
–
A compound switches parts with an element
Pattern
A + BC  B + AC
Always has one element and one compound on
each side
Examples
•
•
Cu + 2AgNO3  2Ag + Cu(NO3)2
2K + 2H2O  H2 + KOH
Types of Reactions
What are the general types of reactions?
•
Double Replacement (Displacement)
–
–
–
–
–
Two compounds switch parts
Often results in the formation of a precipitate
Pattern
AB + CD  AD + CB
Always has two compounds on each side
Examples
•
•
Pb(NO3)2 + 2KI  PbI2 + 2KNO3
CaCO3 + 2HCl  CaCl2 + H2CO3
Types of Reactions
What are the general types of reactions?
•
Combustion
–
–
–
–
–
Reacts rapidly with oxygen
Everything combines with oxygen
Pattern
AB + O2  AO + BO
Always has oxygen as a reactant
Examples
•
•
CH4 + O2  CO2 + 2H2O
2Ca + O2  2CaO
S-138
•
Balance the following reactions and tell
what type(s) they are.
1. Pb(NO3)2 + HCl  PbCl2 + HNO3
2. Ca + HCl  CaCl2 + H2
S-139
•
Write out the reaction, then balance it and
tell what type it is.
1. Mercury reacts with oxygen to form
Mercury (II) Oxide
S-140
•
Write out the reaction, then balance it, tell
what type it is and calculate the molar
mass of the compound
1. Iron (III) Chloride is produced by the
reaction of Iron (III) Oxide and Lead (II)
Chloride. Lead (II) Oxide is also
produced.