Finals. ;__;

Ewww. Finals. What every student dreads at the end of the year. If this was elementary or middle school, we would be having parties all day this week, but no, high school is evil and we have to have finals. I am such a retard. D:

I have all A's in all my classes... except Jackson. AUGH.
I got a 50% on my Cyrano essay final and it dropped my grade to an 86.9%. Now the only things I have left to raise my grade to a borderline A- are some last minute quizzes, extra credit, and THE FINAL. But the worst part is, I never get good grades on my finals. I always rely on my high grade to shield me from the drop in my percentage after bombing one. LOL, THE IRONY

So yeah. I liked Joy Luck Club, but I am just really anxious for the essay. I hope I get an A and Jackson will be nice and if I get a B+ he'll raise it to an A-. T_T Then my mom won't be all "WTF" at me. :C

Mini Project #3: Homemade Ice Cream

To demonstrate the properties of lowering the freezing point of something, we made homemade ice cream in class today. It was really yummy :) (although there was water and salt and ice everywhere! x.x)



Photocredit: Theresa Anselmo

To make our homemade ice cream, we put 1 cup of milk into a ziploc baggie and added two tablespoons of sugar and some vanilla extract. Then we sealed it off and put it into a bigger ziploc bag with lots of ice and 1/3 cup of salt in it, and sealed that too. After we shook it for about 5 minutes, the milk would begin to solidify and it would turn into some delicious ice cream :)

But how does this work? When the salt comes in contact with the ice, the salt lowers the melting point of the ice, making it really really cold, allowing the ice cream to solidify.

Mini Project #2: Frozen Water Balloon

Instead of being boring and just making a balloon filled with water, I decided to throw it in the freezer for fun. What did I get?

This.



Photocredit: Myself

It's a frozen water balloon! I thought the rubber would crack from the ice forming (think frostbite), but rubber is extremely flexible and didn't crack at all. It's structure allows it to stretch itself and fit to almost anything!

How to make a frozen water balloon:
1. Fill a balloon with water
2. Tie the balloon off
3. Put the balloon in the freezer for one day
4. Voila! Your very own lethal cool frozen water balloon!

Chem Standard Post

ChemStd 5a: Students know the observable properties of acids, bases, and salts.



Acids and bases are substances that donate and receive protons. They are rated based on a pH scale from 0 to 14.

Acids are proton donating substances that give away protons when aqueous. Examples of some acids include hydrogen chloride (HCl), carbonic acid (H2CO3), and citric acid in lemons and oranges.

Some properties of acids:

they are corrosive

they taste sour

they neutralize bases

pH is less than 7

blue to red, acid

Bases are substances that receive protons, namely from acids. Bases can be found in many cleaning products like soap. Examples of bases include ammonia (NH4), caustic soda (NaOH), and milk.

Some properties of bases:

they are corrosive

they feel soapy

they taste sour

have pH more than 7

red to blue, baseroo



Salts are ionic compounds that result when you mix an acid and a base together. It's composed of a metal and a nonmetal cation and anion. When you put salts in water they dissolve and separate into their ions. Common table salt (NaCl) is the best known example of a salt.

Some properties of salts:

they are ionic

crystallized structure

dissolve in water

conduct electrical current in water

high melting point

brittle

Mills Canyon Field Trip

I didn't go on the field trip on Thursday. :D School was the same just as usual and all xD


View Mills Canyon in a larger map

This is the path to and through Mills Canyon. Pictures credit to Mr. Olson.

Mini-Project #1: Invisible Ink

Materials:
# Half a lemon
# Water
# Spoon
# Bowl
# Cotton Bud (Swab, Ball)
# White Paper
# Lamp or other light bulb

Procedure:

1. Squeeze some lemon juice into the bowl and add a few drops of water.
2. Mix the water and lemon juice with the spoon.
3. Dip the cotton bud into the mixture and write a message onto the white paper.
4. Wait for the juice to dry so it becomes completely invisible.
5. When you are ready to read your secret message, heat the paper by holding it close to a light bulb.

Safety Precautions:
# Safety first, goggles on!
The acid from the lemon can burn your eyes and cuts on your skin.

Scientific Principles:
Since lemon juice is acidic and also organic, an oxidation reaction occurs when heat is applied and the words will turn brown. Any other acidic substances will work as well. Theresa and I used vinegar as a substitute (since squeezing lemons is rather dangerous xD)


Me and Theresa. Photocredit to Marcia Lee!

Well apparently our project half-failed because we didn't have a lightbulb to use as a light source, and the fire was a little too dangerous xD! The message reads "HI! WE <3 CHEM!"

iProposeWe

How to Make Glow-in-the-Dark Slime
How to Make Glow-in-the-Dark Slime (with similar instructions)

Materials needed:

Elmer's glue gel or 4% polyvinyl alcohol solution

4% (saturated) borax solution

phosphorescent zinc sulfide (ZnS) or glowing paint

measuring cups/spoons

bowl or ziploc baggie

spoon (optional)

Procedure:
1. Make a 4% polyvinyl alcohol solution. Another substitution is one part regular school glue, mixed with three parts water.
2. Mix zinc sulfide into the polyvinyl alcohol solution (approx. 0.6ml ZnS per 30ml of solution). Or, use glow-in-the-dark paint found at arts and crafts stores.
3. Make a 4% saturated borax solution.
4. Mix 3 parts of the PVA or glue gel solution with 1 part borax solution, and slowly mix inside a sealed baggie with a spoon or with your hands.

Safety Precautions:

Don't eat or inhale the slime or any of the ingredients

Always wash your hands after using the slime

Scientific Principles:
1. Slime is made up of polymers.
2. The borax acts to connect the glue molecules, creating chemical polymers, which makes slime.
3. Zinc sulfide has a special physical chemical property of glowing in the dark.