Happy FRIDAY! 
11/30/2012
DO NOW!
1. Are most elements on the periodic
table metals, nonmetals, or
metalloids?
2. Why are metals commonly used for
cookware?
3. Plastic is an insulator. Explain what
this means.
4. What does ductile mean?
Create a SMALL T-chart under your Do
Now and write down your
observations
Tearing Paper
Burning Paper
LEQ #5
• What is the difference between a physical and
chemical change?
• Create another T-chart underneath. (Take up
the whole page)
Physical Change
Chemical Change
• Tearing paper and Burning paper?
Physical Change (NOTES)
• A change that does NOT change the
identity of the substance
• ex:
–Tearing paper
–Melting ice, Boiling water and Freezing
water (change in state or phase)
Chemical Change (NOTES)
• Change in appearance AND chemical
make-up -- a NEW substance is formed.
• Irreversible
• A chemical reaction occurs.
• Ex:
–Burning paper
–Digesting Food
Chemical Change (NOTES)
Signs of a Chemical Change :
– Color change
– Light and Heat is produced
– A gas forms (bubbles)
– Precipitate forms
• A solid forms from a chemical reaction that takes
place in a solution
Brainpop Video
• Write down at least TWO examples of:
• Physical change
• Chemical Change
In your T-Chart
Hypothesis
• I think that the difference between a physical
change and a chemical change is….
• Think - Pair - Share
Hot Question!
Which is an example of a physical change?
A. Boiling
B. Burning
C. Rotting
D. Rusting
Experiment
• Tell if each example is a chemical change or a
physical change.
• Be ready to explain why…Ms. K will randomly
pick a team member to explain for the point.
• Add the correct answer to your T-chart in your
notebook.
Melting Ice
Chopping Wood
Mixing Salt and Water
Breaking Glass
Burning Wood
Melting Iron
Melting Ice Cream on a hot day
Digesting an apple
Boiling Water
Cooking an egg
Mixing Peas and Carrots
Bicycle rusting
LAB TIME!
• Perform each station of the lab (I will lead you in
the first station).
• Lab:
– Follow the procedure carefully!!!
– Make observations of the change that is occurring
– Is this an example of a physical change or a chemical
change?
– Explain how you know.
Data Collection
•
•
•
•
Discuss your answers with another group…
Did you both get the same conclusions?
Why or why not?
Debate (respectfully)… who was right? Why?
Data Analysis (NOTES)
How can you tell the difference between a chemical
and physical change?
• Signs of a Chemical Change
–Light and heat is produced
–A gas forms
–Color change
–Precipitate forms
• A solid forms from a chemical reaction
that takes place in a solution
Add Examples to your T-Chart
• Salt water boiling
• Vinegar and baking soda combining
What about a Mixture? Compound?
Add to your T-chart
Your turn!
• Read one through 10 and decide if it is a
physical change (P) or Chemical Change
(C)
• The next blank you must explain why?
What sign did you see of a chemical
change
• You have 7 minutes!
Answer LEQ on back of EXIT TICKET
• Day 1: (Hint: there are 4 signs…)
• Ms. K mixes 2 substances and passes
around the flask for students to
observe. She tells them a chemical
reaction (change) has taken place.
How do the students know?
Day 2
LEQ 9
Chemical Reactions
• Homework: Chemistry questions due TODAY
• # 23 should be C (Boron is the only metalloid)
• Do Now: add these words
Physical Change – draw a picture
Chemical change – draw a picture
Participate – draw a picture
• Chemical reaction
• Reactant
• Product
• Coefficient
• Subscript
1. Which is only a
physical change?
souring or milk
melting of ice
burning of oil
rusting of iron
HOT Qs
2.Which process involves
a chemical change?
Photosynthesis
freezing water
boiling water
melting ice
3. In the making an
omelet, which process
involves a chemical
change?
melting butter
frying eggs
chopping onions
stirring eggs
Chemical Reactions
• Watch the video and watch for REACTIONS
–Are they chemical or physical changes
do you think?
• http://www.youtube.com/watch?v=90FR8mzEH4
So… What is a Reaction?
Give me some examples from the
video and life…
• a response to something
NOTES
• Chemical reaction-when two or more
substances interact and a chemical change
occurs
– Ex. Rust, when Iron (Fe) combines with Oxygen
(O) in the air
– NOT an ex. When water (H2O) evaporates (still
H2O)
• Reactant + Reactant  Product
– Example: Carbon + Oxygen  Carbon Dioxide
Reaction in a Bag!
• Turn in your notebooks to “Signs of a
Chemical Change” from yesterday. Be on the
lookout to see which of these signs occur in
our experiment.
• Combine: steel wool, Yeast and hydrogen
peroxide
• What happened? How did you know?
1. Pour the baking soda into the Ziploc
2. Put the steel wool into the Ziploc
3. Pour your hydrogen peroxide (or is it
vinegar?) into the bag, then QUICKLY zip it
up!
4. Shake it like a Polaroid picture.
5. Fill out the chart in your notebook and
answer the question with your group.
Hot Question!
What type of change has occurred when a
statue changes from it’s original color due to
acid rain?
A.The statue has been painted
B.Physical change
C.Physical weathering
D.Chemical change
Testable Question
• How can we represent chemical reactions?
• Brainpop video
NOTES
• Chemical Equations: how scientists
represent chemical reactions
6 CO2 + 6 H2O  C6H12O6 + 6 O2
NOTES
6 CO2 + 6 H2O  C6H12O6 + 6 O2
Reactants
Products
Chemical Reaction
Coefficient
Subscript
NOTES
• Reactants: substances that take part
in a chemical reaction
• Chemical Reaction: process by which
new substance is formed
• Products: substances made during a
chemical reaction
NOTES
• Coefficient: # of molecules of a
compound in a chemical
reaction
• Subscript: # of atoms of an
element in a compound
Experiment
2 H202 2 H20 + O2
2 (H202)  2 (H20) + O2
1.Reactants?
2.Products?
3.How many molecules of H20 are in the products?
4.How many atoms of Hydrogen are in H202?
5.How many atoms of Hydrogen are in the Reactants?
Experiment (Notes)
C3H8 + 5 O2 
C3H8 + 5 (O2 ) 
4 H2O + 3 CO2
4 (H2O) + 3 (CO2 )
1.Reactants?
2.Products?
3.How many molecules of H20 are in the products?
4.How many atoms of Hydrogen are in C3H8?
5.How many atoms of Hydrogen are in the Reactants?
Experiment
4Al + 3 O2  2 Al2O3
4(A)l + 3 (O2 )  2 (Al2O3 )
1.Reactants?
2.Products?
3.How many molecules of Al203 are in the products?
4.How many atoms of Oxygen are in O2?
5.How many atoms of Oxygen are in the Reactants?
Experiment
6 CO2 + 6 H2O  C6H12O6 + 6 O2
1.Reactants?
2.Products?
3.How many molecules of C02 are in the reactants?
4.How many atoms of Hydrogen are in H20?
5.How many atoms of Hydrogen are in the Reactants?
What in the world is a precipitate?
• http://www.youtube.com/watch?v=8RmVwz2
fNGc (shorter)
• OR
• http://www.youtube.com/watch?v=JAeOP2Mf
rDY&feature=related (longer)
Finding the main idea and
supporting details!
(20 min. 4 min/paragraph)
• Read the article about reaction rates.
• For each paragraph, write down the main idea
and 2 supporting details
• 1 reader and 1 recorder
• Reader reads aloud
• Recorder writes down the main idea and
supporting details
• Switch for each paragraph
Factors that affect the RATE of a
chemical change (NOTES)
• Rate—how
quickly
something
happens
Factors that affect the RATE of
chemical change (NOTES)
• Temperature
• Surface area
• Concentration
HOT Q
Which factors will increase solubility of a solute
dissolving in a solvent?
A.Decrease temperature and surface area
B.Decrease temperature and increase surface
area
C.Increase temperature and surface area
D.Increase temperature and decrease surface
area
Ms. Honeycutt will place an alka seltzer in a film
canister with:
1. Water
2. Hot water
3. Tablets
4. Crushed Tablet
Students will time how long it took for the
reaction to take place
Data Collection
• Record data in the table below:
Trial
1(water)
2 (hot
water)
3 (2
tablets)
4 (crushed
tablet)
Time
Reaction Rates Race!
• Answer the conclusion questions about
reaction rates.
• It gets harder as you answer more questions
• If you get stuck, use your article as your
solution station (it has all the answers!)
Answer the LEQ
• Day 2: How could Ms. Honeycutt have
increased the rate of the reaction?