Chemical Changes
October 7,
2015
DO NOW:
Date: October 7, 2015
TEKS: (Yes, write the WHOLE thing!)
6.5 D identify the formation of a new substance by using the
evidence of a possible chemical change such as production of a
gas, change in temperature, production of a precipitate, or
color change.
1.
2.
3.
4.
Pick up a new gold Do Now sheet
Put your CB on your desk
Copy down this week’s TEKS
Write this week’s homework in your agenda: Read
pages 138 – 148 in Science Fusion. Complete p.149,
tear out, and turn in by Friday!
4. Q?: Give 5 examples of physical changes.
5. Get your computer from the cart and log in
Ms. Smith
Mrs. Malone
• Homework: Read
pages 138 – 148 in
Science Fusion.
Complete p.149, tear
out, and turn in by
Friday!
• Announcements:
– Tutorials Tuesday
– Fresh Start! It’s a new
6 week marking period
•
•
•
•
PhET Simulation (Google Chrome!)
http://phet.colorado.edu/en/simulation/build-a-molecule
Click on the green “Run Now” box
Wait for the simulator to load and press “Run”
If you get a security warning at the bottom of the screen,
press “Keep”
• Click the downloaded program in the bottom left corner of
the browser. If you get a Java update message, just press
“Later”
• Press “Run” and explore the program! Be sure to fill out
your paper as you explore.
–
–
–
–
Make molecules and drag them to your collection.
Click “Refill Kit” if you run out of atoms and need more.
Click the yellow arrow if you need a different kind of atom.
Move onto the next collection after you complete your student
sheet for collection 1.
– Complete Collections 1 – 4
Chemical Changes
DO NOW:
Date: October 6, 2015
6.5 D identify the formation of a new
substance by using the evidence of a
possible chemical change such as
production of a gas, change in temperature,
production of a precipitate, or color change.
1. Put your CB on your desk
2. Get your computer and turn it on.
Answer the Do Now question while
your computer loads.
3. Q?: What are compounds made of?
October 6,
2015
Ms. Smith
Mrs. Malone
• Homework: Read
pages 138 – 148 in
Science Fusion.
Complete p.149, tear
out, and turn in by
Friday!
Chemical Changes
October 6,
2014
Ms. Smith
Mrs. Malone
Chemical changes occur when matter has
changed into a new substance through a chemical
reaction. Signs of a chemical reaction include:
 color change
 gas produced (bubbling, fizzing, smoke)
 solid precipitate
 temperature change
 exothermic = hot
 endothermic
= cold
:
Demonstration
• Copper (II) Sulfate + Ammonia
• Did a chemical reaction occur?
• What was the sign of a chemical change?
Chemical Changes Presentation
•
•
•
•
•
•
www.ohenryscience6.weebly.com
Click on Handouts
Download the file
Press F5 to make the presentation full screen
Complete your Cornell Notes on your own
Finished early? Continue working on
yesterday’s PhET simulation!
Chemical Changes
DO NOW:
Date: October 7 - 8, 2015
6.5 D identify the formation of a new substance
by using the evidence of a possible chemical
change such as production of a gas, change in
temperature, production of a precipitate, or color
change.
1. Things are going to be messy today.
Make sure your backpack is UNDER your
table
2. Q?: What signs of a chemical reaction
do you observe in the animation?
Pictured: A gummy bear (made of glucose)
reacts with potassium chlorate
October 7 - 8,
2015
Ms. Smith
Mrs. Malone
• Homework: Read
pages 138 – 148 in
Science Fusion.
Complete p.149, tear
out, and turn in by
Friday!
Group Member Roles
October 7 - 8,
2014
Ms. Smith
Mrs. Malone
Green - Materials Manager
• Obtains and returns all lab materials
Yellow – Safety/Clean-up Manager
• Enforces all safety rules (Goggles and Glass!!)
Blue - Activity Director
• Reads directions to the group
• Keeps group on-task
Red - Data Manager
• Ensures all group members have lab data
:
Chemical Changes
October 6,
2014
Ms. Smith
Mrs. Malone
Chemical changes occur when matter has
changed into a new substance through a chemical
reaction. Signs of a chemical reaction include:
 color change
 gas produced (bubbling, fizzing, smoke)
 solid precipitate
 temperature change
 exothermic = hot
 endothermic
= cold
:
Evidence of a chemical change.
1. Formation of a gas
 Bubbles, fizz, or smoke form
when a new substance is
produced. Listen for the sound
of bubbles popping!
 Watch out! Shaking something
to create bubbles and opening a
can of pressurized soda to
release the CO2 are not
chemical changes!
Chemical Change
2. Color Change
◦ The product is a new color that was
not there before
◦ Watch out! Adding a dye (like paint
or food coloring) to change the color
of something is NOT a chemical
change
Chemical Change
3. Temperature Change
• The new substance is hotter
(exothermic) or colder
(endothermic) than the substances
that formed it
• Watch out! Sometimes substances
change temperature because YOU
alter them, not from a chemical
reaction!
– Heating a substance (microwave, hot
plate, flame, etc.)
– Cooling a substance (with ice, in the
refrigerator, in the freezer, etc.)
Chemical Change
4. Formation of a
Precipitate
• A precipitate forms when a
substance comes out of
solution and forms a new
solid that wasn’t there
before
• Watch out! Freezing is a
physical change, not a
chemical change!
Universal Indicator
• A chemical change occurs when universal indicator is
added to acids and bases
– Universal indicator is an indicator, because it contains
molecules that change color when an acid or base is
added to them. Compare your samples to the key.
Mystery Powders Steps for Success
• Each powder has its own numbered
column. Use the index cards to keep the
powders separated when adding to the
wells
• Describe all 6 powders BEFORE reacting
(color, texture, state of matter)
• Describe all 4 liquids BEFORE reacting
(color, smell, state of matter)
• Do NOT touch the dropper bottle tips to
the powders or you will contaminate the
entire bottle!!
• GOGGLES ON AT ALL TIMES.
MICROCHEMISTRY PLATES WILL SPLASH
WHEN RINSED!
Mystery Powders Analysis and
Conclusion
• Fill in your data table – no blanks! Write “No
reaction” if there was no reaction
• Answer the analysis questions with your
group and support your answers with your
data
• Write a conclusion for Mystery Powders using
Page 3 Lab Resources – Lab Conclusion Guide
from your interactive notebook (comp book)
• TURN IN YOUR LAB REPORT PAPER today for a
grade
Chemical Change
• A chemical change occurred when universal indicator was
added to cream of tartar and laundry detergent.
– Universal indicator is an indicator, because it contains
molecules that change color when an acid or base is
added to them.
– Cream of tartar is an acid, so it gave particles to the
indicator, making it turn from purple to red.
– Laundry detergent is a base, so it took particles from
the indicator, making it turn from red back to purple.
Is It a Chemical Change?
Whiteboard Review
• Write YES if the example shows signs of a
chemical change
• Write the sign(s) that prove that the example
is a chemical change
• Write NO if the example if not a chemical
change
• Explain why it is a physical change and not a
chemical change
Is it a chemical change?
A forest fire destroys acres of
land. There is a lot of
smoke, and the trees turn
to charcoal.
ANSWER:
EVIDENCE:
YES
- color change,
- temperature change
Is it a chemical change?
When making hot cocoa, clear
water turns brown when
you mix the cocoa in.
ANSWER:
No
(the water is turning brown
because the cocoa is brown)
Is it a chemical change?
An old wheelbarrow is left out
in the rain and rusts.
ANSWER:
Yes
EVIDENCE: Color change, precipitate forming (rust)
Is it a chemical change?
On a hot day, water forms on
the outside of a cold glass
of water.
ANSWER:
No
(No new substance is forming)
Is it a chemical change?
Ice cream melts after it falls
on the ground.
ANSWER:
No
(No new substance is forming)
Is it a chemical change?
A raw egg gets cooked.
ANSWER:
Yes
EVIDENCE: Color change
Is it a chemical change?
When Alka Seltzer is
dropped into water it
fizzes.
ANSWER:
Yes
EVIDENCE: gas formation
Is it a chemical change?
Crayons change white paper
to red.
ANSWER:
No
(The paper is turning red because the crayon is red.)
Is it a chemical change?
Soda fizzes, and bubbles rise
as you pour it in a glass.
ANSWER:
No
(The bubbles were already there, just under pressure in the
bottle.)
Is it a chemical change?
When you crack a glow stick,
hydrogen peroxide mix with
other chemicals, causing it
to glow and warm up.
ANSWER:
EVIDENCE:
Yes
- color change
- temperature change
Chemical Changes
DO NOW:
Date: October 9, 2015
6.5 D identify the formation of a new
substance by using the evidence of a
possible chemical change such as
production of a gas, change in
temperature, production of a precipitate,
or color change.
1. Turn in your homework!
2. Get out purple Do Now sheet –
due today!
3. Q?: What are the 4 signs of a
chemical reaction?
October 9,
2015
Ms. Smith
Mrs. Malone
Reminders:
– Did you turn in your
Chemistry in the
Kitchen Homework?
To Do: Friday, October 10th
1. Complete “Mystery Powders” initial
observations, data table, analysis questions,
and conclusion (using page 3 lab conclusion
guide) and TURN IT IN today.
2. Complete PhET Molecules simulation and
Chemical Changes Notes
3. Check your science journal for completion. Use
my sample comp book as a guide! My journal
has 29 complete pages. Yours should too!