Types of Chemical Reactions - Ms
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Transcript Types of Chemical Reactions - Ms
Chemical reactions can be classified in one
of two ways:
1. Based on how atoms are reordered
2. Based on how energy/ heat is transferred
Two or more elements/compounds combine to
form a single product.
General equation: A + B AB
2Mg + O2 2MgO
A
B
AB
2Mg + O2 2MgO(white powder)
A + B AB
8 Fe + S8 8 FeS
+
A single reactant/compound, breaks into
two or more parts.
General equation: ABA + B
o
AB
2H2O2 2H2O + O2
A
B
2H2O2 2H2O +O2
AB A + B
Bubbles are O2
Liquid is water.
Elephant’s
toothpaste
MgO2 Mg
+ O2
+
+
A
BC
AC
B
A more reactive Single element replaces a less
reactive element in a compound. (metal replaces
another metal… a non-metal replaces a nonmetal)
The general equation:
(Rico Suave Scandal)
A + BC AC + B
Al + CuCl2 AlCl3 + Cu
A + BC BA + C
Mg + 2HCl MgCl2 + H2
A + BC BA + C
What do you know about
Hydrogen gas!?
2Mg +2HCl 2 MgCl
_____ + H
_____
2
If a metal will only replace a metal, and a
non-metal will only replace a non-metal…
then what will the products be??
Mg kicks out H so that Mg can bond with
Cl.
BUT WAIT!!! H is the leader of the NOF 7
group – so it’s diatomic!
BUT WAIT!!! Is it balanced??
MgCl2 + __________
Al
Mg + AlCl3 ________
NaCl + __________
Br2
Cl2 + NaBr ________
Copper(II) + silver nitrate yields …
Ag(NO3) Cu(NO3)2
Ag
Cu _______
_____+
_________ + _______
Single Replacement
+
+
Single Replacement
+
+
CD
AB
CB
AD
Two compounds switch partners to form two
new compounds
General equation: AB + CD AD + CB
KI+ Pb(NO3)2 KNO3 + PbI
Note: “Metals” replace “metals” and non-metals
replace non-metals
Scandal of Scandals!!
KI(aq) + Pb(NO3)2(aq) KNO3(aq) + PbI(s)
AB + CD
AD + CB
CaCl2+ ________
MgCl2+ Ca(SO4) _____
MgSO4
If a metal will only replace a metal, and a nonmetal will only replace a non-metal… then
what will the products be??
Mg kicks out Ca so that Mg can bond with SO4.
BUT WAIT!!! Make sure CaCl has the right
formula. (Ca2+ … Cl 1-)
BUT WAIT!!! Is it balanced??
+
+
Double Replacement
Double Replacement
Pb (NO3)2 + K I
Pb(NO3)2 + K I KNO3 + PbI2
+
+
C H
A hydrocarbon or alcohol is reacted with
oxygen gas to always form the products carbon
dioxide and water.
General equation:
Hydrocarbon + O2 CO2+ H2O
or Alcohol
CH4 + O2 CO2 + H2O
C10H8 + 12 O2 ---> 10 CO2 + 4 H2O
Combustion
Hint: Look for CO2
and H2O as products!!
Unfortunately we cannot forget about neutralization reactions (a.k.a. acidbase reactions)!
Acid and a base react to form a salt and
water.
General equation: HX + MOH MX +H2O
HCl + NaOH NaCl + H2O
Where M is a metal and X is a non-metal
HBr + NaOH ---> NaBr + H2O
Neutralization
1.
EXOTHERMIC (exo= outside)- energy is released
as a product during a chemical reaction given off
as heat (hot rxn!!)
H2O2 O2 + H2O + Heat (heat is a product)
1.
ENDOTHERMIC (endo= inside)- energy is required
(a reactant) during a chemical reaction and heat is
absorbed (cold rxn!!)
2NH4 + H2O + Heat 2NH4(OH) (heat is a reactant)
Brrr…
Sodium acetate
in water