Download 2014-01-10_BalancingChemRxns

January 10, 2014
AGENDA:
1 – Bell Ringer
2 – Review HW
3 – Cornell Notes: Balancing
Chemical Reactions
4 – Practice
5 – BrainPop: Chemical
Equations
Today’s Goal:
Students will be able to balance
chemical reactions.
Homework
1.
Balancing Chemical Reactions
Practice Problems
2.
Next week is the last week
before exams! So make sure to
finish any missing work this
weekend to turn in by next
Friday at the LATEST!
Friday, January 10
Objective:
Students will be able to balance chemical reactions.
Bell Ringer:
Classify the following reactions: (as synthesis (S),
decomposition (D), combustion (C), single-replacement (SR)
or double-replacement (DR))
1.
2.
3.
FeCl3 + NaOH  Fe(OH)3 + NaCl
N2 + H2  NH3
Ag2O  Ag + O2
4 MINUTES
REMAINING…
Friday, January 10
Objective:
Students will be able to balance chemical reactions.
Bell Ringer:
Classify the following reactions: (as synthesis (S),
decomposition (D), combustion (C), single-replacement (SR)
or double-replacement (DR))
1.
2.
3.
FeCl3 + NaOH  Fe(OH)3 + NaCl
N2 + H2  NH3
Ag2O  Ag + O2
3 MINUTES
REMAINING…
Friday, January 10
Objective:
Students will be able to balance chemical reactions.
Bell Ringer:
Classify the following reactions: (as synthesis (S),
decomposition (D), combustion (C), single-replacement (SR)
or double-replacement (DR))
1.
2.
3.
FeCl3 + NaOH  Fe(OH)3 + NaCl
N2 + H2  NH3
Ag2O  Ag + O2
2 MINUTES
REMAINING…
Friday, January 10
Objective:
Students will be able to balance chemical reactions.
Bell Ringer:
Classify the following reactions: (as synthesis (S),
decomposition (D), combustion (C), single-replacement (SR)
or double-replacement (DR))
1.
2.
3.
FeCl3 + NaOH  Fe(OH)3 + NaCl
N2 + H2  NH3
Ag2O  Ag + O2
1 MINUTE
REMAINING…
Friday, January 10
Objective:
Students will be able to balance chemical reactions.
Bell Ringer:
Classify the following reactions: (as synthesis (S),
decomposition (D), combustion (C), single-replacement (SR)
or double-replacement (DR))
1.
2.
3.
FeCl3 + NaOH  Fe(OH)3 + NaCl
N2 + H2  NH3
Ag2O  Ag + O2
30 seconds Remaining…
Friday, January 10
Objective:
Students will be able to balance chemical reactions.
Bell Ringer:
Classify the following reactions: (as synthesis (S),
decomposition (D), combustion (C), single-replacement (SR)
or double-replacement (DR))
1.
2.
3.
FeCl3 + NaOH  Fe(OH)3 + NaCl
N2 + H2  NH3
Ag2O  Ag + O2
10 Seconds Remaining…
BELLRINGER
TIME IS
UP!
January 10, 2014
AGENDA:
1 – Bell Ringer
2 – Review HW
3 – Cornell Notes: Balancing
Chemical Reactions
4 – Practice
5 – BrainPop: Chemical
Equations
Today’s Goal:
Students will be able to balance
chemical reactions.
Homework
1.
Balancing Chemical Reactions
Practice Problems
2.
Next week is the last week
before exams! So make sure to
finish any missing work this
weekend to turn in by next
Friday at the LATEST!
Cornell Notes


Reflection
Question:
Why do
we
balance
chemical
equations?
Topic: Balancing Chemical Reactions
Date: 1/10/2014
MgO  Mg + O2
Reactants  Products
Things
reacting
Things
produced
Cornell Notes (continued)
Law of Conservation of Mass/Matter =
Mass of
reactants
# of each
element of
the reactants
=
Mass of
products
=
# of each
element of
the products
Cornell Notes (continued)
Example:
Coefficients
Reactants
___
2 MgO
Products
___
2 Mg + ___
1 O2
Mg = 1 x 2 = 2
O=1 x2=2
= Mg
= O
Mg = 1 x 2 = 2
O=2x1=2
Balanced Chem. Eqn. =
2 MgO  2 Mg + 1 O2

+
Cornell Notes (continued)
“How to Balance” Steps:
1.
Draw a line between reactants & products.
2.
Count up all atoms of reactants & products.
3.
Determine multiplier (coefficient)  LCD (Lowest
Common Denominator).
4.
Place multiplier (coefficient) in front of compound.
5.
Repeat as necessary until all elements are
balanced.
Practice
Counting Atoms:
O2
O = 2
Fe2O3
Fe = 2
O = 3
2 NaOH
Na = 2
O = 2
H = 2
2 Ca(NO3)2
Ca = 2
N = 4
O = 12
…or…
…or…
2 NaOH
Na = 2
OH = 2
2 Ca(NO3)2
Ca = 2
NO3 = 4
Practice (continued)
Example:
Reactants
___
2 Ag + ___CuCl
1
2
Ag = 1 x 2 = 2
Cu = 1 x 1 = 1
Cl = 2 x 1 = 2
Products
___
1 Cu + ___
2 AgCl
Ag = 1 x 2 = 2
Cu = 1 x 1 = 1
Cl = 1 x 2 = 2
Reflection

In the summary section of your Cornell Notes,
complete both of the following sentence strands in 5
minutes:
 It
is important to balance chemical equations
because…
I
can balance chemical reactions by…
BrainPop: Chemical Equations
http://www.brainpop.com/science/matter
andchemistry/chemicalequations/