February 22, 2012

AGENDA:1 – Bell Ringer & Part.

Log2 – Return Quiz3 – Cornell Notes:

Balancing Chemical Reactions

3 – Work Time

Today’s Goal:Students will be able to

balance chemical reactions.

Homework1. Finish Practice

Problems2. Up-to-date Notebook3. Friday is the Last Day

to take Last Week’s Quiz

4. Last Week’s Work is due by Friday at the latest

Cornell Notes

Topic: Balancing Chemical Reactions

Date: 2/22/2012

MgO Mg + O2

Reactants Products

Why do we

balance chemica

l equatio

ns?

Things reactin

g

Things produc

ed

Cornell Notes (continued)

Law of Conservation of Mass/Matter =

=

=

Mass of reactant

s

Mass of product

s

# of each element of

the reactants

# of each element of

the products

Cornell Notes (continued)

Reactants___ MgO

Mg = 1 O = 1

Products___ Mg + ___ O2

Mg = 1 O = 2

Example:

x 2 = 2x 2 = 2

x 2 = 2x 1 = 2

2 2 1

Balanced Chem. Eqn. =2 MgO 2 Mg + 1 O2

= Mg= O +

Coefficients

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.4. Place multiplier (coefficient) in front

of compound.5. Repeat if necessary.

Practice (on LEFT page)

Counting Atoms:

O2 O = 2

Fe2O3 Fe = 2O = 3

2 NaOH Na = 2O = 2H = 2

2 Ca(NO3)2 Ca = 2N = 4

O = 12

Practice (continued)

Reactants___ Ag + ___CuCl2

Ag = 1 Cu = 1 Cl = 2

Products___ Cu + ___ AgCl

Ag = 1Cu = 1

Cl = 1

Example:

x 2 = 2x 1 = 1

x 2 = 2x 1 = 1

2 1 21

x 1 = 2

x 2 = 2