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bjbjLULU In science Class, we have been studying Chemical and Physical Changes. SHAPE \* MERGEFORMAT
light or energy. s look at a physical change. I have a cup full of H2O in it s liquid form,
otherwise known as water. We will add 5 drops of purple food coloring. (Add drops) We can
observe that the two matters have combine. We see that the water, which was clear, is
now light purple. And the food coloring, which was dark purple is now lighter. But, we still
have H20 (water) and food coloring! Did our temperature change? No. did it give off light?
No. Could we get our food coloring back, if we wanted to? Yes. How? Just leave this in
the lab in Ms. M s room until the water evaporated (or turned to a gas). Then only the purple
dye will be left in the cup! Excellent! Then this is DEFINITELY a Physical Change. I think
I get it, but could we see one more example of Physical change? Sure! No Problem! What
experiment do you have? well, I have polystyrene and acetone. My polystyrene is in the form
of a foam cup. When I put this cup into the acetone, it, well . . . . . just watch. (Push
cup into acetone) Now, while it looks like this surely was a Chemical change, if you
look into the bowl, you will see that we STILL have acetone and polystytrene. All that has
happened is wthat we broke the foam into smaller pieces that let the air that was between the
molecules, escape. s STILL polystyrene, it s just not puffed up into a cup anymore! I
can prove it! (check thermometer) There was NO temperature change, no light or energy
was taken or given-off. This was a very cool change, but never-the-less a Physical change.
OK. I think I get it, but then what is a Chemical Change? well, a Chemical change causes a change
in properties so what you start with and what you end up with are two different things.
Oh, and don t forget, a chemical change also either takes in or gives off heat, light or
energy! OK. But can you give us an example? N 6 & N7 Sure! In both of these jars are two
identical pennies. We placed a chunk of clay in the bottom of each jar to hold the pennies.
Then we added vinegar to one jar and waited. It has been two weeks. Lets look at the two
pennies to compare them like scientists do! (Reveal both) This penny has been in an environment
of regular air, just like what s around us right now. So this penny hasn t really changed.
But pennies are partially made of copper and when copper is exposed to the acetic acid
in the air around it, from the vinegar, it causes a chemical reaction. It forms copper
oxide which is green! And we have evidence that it was a chemical change because when
we check the temperature in the jar with vinegar (check thermometer), we see that it has increased!
So, change in properties? Check! Change in temperature? Check! So that proves it! It
is a chemical change! Let s do one more example of a Chemical change. Ok? (Crowd answers yes.)
(Walking to N8 & 9) What do you have for us? Our experiment uses protein and hydrogen peroxide.
Our portien is this piece of raw liver (pause) and here s our hydrogen peroxide. Watch as
we pour the hydrogen peroxide onto the piece of protein. (WAIT) Wow! That was cool in a
kinda gross way! But how can we be sure that it was a chemical change? Well the temperature
changed from (check thermometer) ____ to _____ degrees and the protein is now grayish in
color and not squishy any more. So what DID we see? Scientifically, speaking. Well, the
bubbles that we say were the oxygen molecules being released, leaving H2O (or water) behind.
So, we have different matter with different properties! N10 Wow! That was definitely some
awesome scientific work! I can t wait to see what we learn in class next! N11 Me either!
Who knew that Science in Ms. M s class could be so cool! Even when it s Gross! Ms. M. Thank
you fourth grade Scientists! Please take a bow (pause) and thank you for watching our
WOW Wednesday presentation: Chemical and Physical Changes! 1/12/2011 Dear Parent(s), Our class
is hosting the WOW Wed presentation next Wed. (1/19). Your child has a role as a speaker
in our presentation that we will give to the entire school. Please help them to be successful
by encouraging them to rehearse their lines and memorize them as much as possible. I realize
that this is a HUGE responsibility and could cause any student a large amount of stress,
however, I also recognize Mr. Hinton s Wow Wed program as an excellent way to help students
to develop life/job skills in the safe environment of their home school. Please let me know if
you have any questions or concerns. ( HYPERLINK "mailto:mcqueenm@talawanda.org" mcqueenm@talawanda.org
, 273-3636). Sincerely, Ms. McQueen Ps: if you would like to watch the presentation,
you are welcome to be part of our audience. Seating is available at the rear of the gymnasium
and our presentation will be from 9:00 9:15am. hhRR h4ru hhRR hhRR hhRR hhRR hhRR In science
Class, we have been studying Chemical and Physical Changes Marsha Normal Marsha Microsoft
Office Word Hewlett-Packard In science Class, we have been studying Chemical and Physical
Changes Title _PID_HLINKS Microsoft Office Word Document MSWordDoc Word.Document.8