Download PPT - Reaction Types

Reaction Types
Synthesis
• Synthesis reactions occur when two
substances (generally elements) combine
and form a compound.
• Basically: A + B  AB
• Example: 2H2 + O2  2H2O
An Synthesis Example
Decomposition
• Decomposition reactions occur when a
compound breaks up into the elements or
in a few to simpler compounds
• 1 Reactant  Product + Product
• In general: AB  A + B
• Example: 2 H2O  2H2 + O2
A Decomposition Example
Practice #1
• Identify each reaction as either
decomposition or synthesis:
• C + O2  CO2
– Synthesis
• 2 HgO  2Hg + O2
– Decomposition
Single Displacement
• Single Replacement Reactions occur
when one element replaces another in a
compound.
• A metal can replace a metal (+) OR
a nonmetal can replace a nonmetal (-).
• Generally: A + BC  AC + B
– Zn + HCl 
ZnCl2 + H2
• Zinc replaces the hydrogen ion in the reaction
Single Displacement
Single Displacement
Double Displacement
• Double Replacement Reactions occur when a
metal replaces a metal in a compound and a
nonmetal replaces a nonmetal in a compound
• AB + CD  AD + CB
• Think about it like “foil”ing in algebra, first and
last ions go together + inside ions go together
• AgNO3 + NaCl  AgCl + NaNO3
Practice #2
• K2SO4 + Ba(NO3)2  KNO3 + BaSO4
– Double Displacement
• NaCl + F2  NaF + Cl2
– Single Displacement
Combustion Reactions
• Combustion
reactions occur when
a hydrocarbon reacts
with oxygen gas.
• Products are always
CO2 and H2O
Combustion
• C4H10 + O2  CO2 + H2O
Finally - Neutralization
• A different kind of double
displacement reaction is
called a Neutralization
Reaction
• An Acid (starts with H)
reacts with a Base
(usually alkali or alkaline
earth metal bonded to
hydroxide)
• H2O is a product
Neutralization Examples
• Ca(OH)2 + H2CO3 --> CaCO3 + 2 H2O
Practice #3
• C4H10 + O2  CO2 + H2O
• Combustion
• Mg(OH)2 + HCl --> MgCl2 + HOH
• Neutralization
Practice and a Movie
• 2 KClO3 ——> 2KCl + 3O2
– Decomposition
– http://sciencestage.com/v/618/potassiumchlorate-gummy-bears-chemistry-chemicalreaction.html
Practice #4
– Mg + 2 H2O ---> Mg(OH)2 + H2
• Single Displacement
– Pb(NO3)2 + 2 KI ---> PbI2 + 2 KNO3
• Double Displacement
– 8 Fe + S8 ---> 8 FeS
• Synthesis
– C10H8 + 12 O2 ---> 10 CO2 + 4 H2O
• Combustion
– 2 H2O ---> 2 H2 + O2
• Decomposition
– HCl + NaOH --> NaCl + H2O
• Neutralization
Chemicals in Action
• http://video.google.com/videoplay?docid=1
775983120224943095&ei=3lDRSZZyjKyo
AvC28eYE&q=chemical+reaction+&hl=en
• http://video.google.com/videoplay?docid=4384238026970994778&ei=hlHRSa_mK5
CarwK5mqHgBA&q=iodine+clock&hl=en
• http://video.google.com/videoplay?docid=6
80106771263243162&ei=71HRSbWULoO
MqwLskviNBQ&hl=en