Tuesday, May 18, 2010

Gravativity

*Yes, the title is purposely spelled wrong.

So this mini-project has actually been proven before, but I still have some doubts to it - do paper and a bowling ball both land at the same time when dropped from a certain height?

For this mini-project, you will need two materials , preferably of a different weight; in this case, I chose:
1. A small styro-foam soccer ball
2. A Washington - one dollar bill

Science:
-Gravity is a field force, or a force that pulls you even if you are at a great distance
-equivalence principle (key): a principle explored by researchers such as Galileo and Einstein that said two objects of a different mass or vacuum composition dropped from a certain height will fall and land at the same time.

My Three Tries:
1) the dollar seemed to hit the ground after the ball; my guess is that since the dollar bill was bent, the friction of air slowed it down.
2) after smoothing the bill out, the time that both objects hit the ground seemed more even.
3) they both hit the ground at the same time! success!

here is Galileo's falling objects lab proven by "mysciences":





Photocredit: Kenneth Lai (Dad)

MiniProject Pt. II

Materials required:
-cup/glass of water filled near the top (but not full!)
-a piece of cardboard or a card

Can we pretend that... LOL jk

So the mini-project I decided to do was to fill a cup with water, put a card on the bottom, and turn the cup upside down, WITHOUT the water splashing out.

How does this magic water and cup work? (Science)

If done correctly, the paper should stick to the cup, with the water still inside, because the air pressure from outside the cup is greater than the pressure inside.

Photocredit: Kenneth Lai

Friday, May 14, 2010

Chem Standard 2E

Objective: Students know how to draw Lewis dot structures.

Drawing Lewis dot structures really isn't too complicated, once you know the steps.

1) Find the total number of valence electrons in the molecule.


Here's a table with some common individual structures.


2) Figure out how many octet electrons the molecule should have, using the octet rule(all atoms want eight valence electrons to be like the nearest noble gas). Use this rule to figure out how many electrons each atom in the molecule should have, then add.
*There are two that do not want eight, being Hydrogen (2) and Boron (6).

3) Subtract the valence electrons from octet electrons [Subtract the answer from number one from number two]. The answer will equal the number of bonding electrons in the molecule.

[Divide the number of bonding electrons by two because every bond has two electrons, thus the # of bonds in the molecule = number of bonding electrons/2]

4) Draw an arrangement of the atoms for the molecule that contains the number of bonds you found in #4 above.

Here are some helpful guidelines:

o Hydrogen and the halogens bond once.
o Oxygen and its family bond two times.
o Boron itself and Nitrogen's family bond three times.
o Carbon and its family bonds four times.

A good thing to do is to bond all the atoms together by single bonds, and then add the multiple bonds until the rules above are followed.

5) Finding number of lone(nonbonding) electron pairs by subtracting the bonding electrons (#3) from the valence electrons (#1). Arrange these around the atoms until they satisfy the octet rule.

--> Then you're done with drawing those Lewis dot structures!

A fine example of drawing a Lewis Dot Structure, specifically - Carbon Dioxide.

Thursday, May 6, 2010

MiLlZ CrE3K C@nY0|\|

So last week, we went to Mills Creek Canyon (that's what the title says, if you couldn't read it). It was a good experience to explore and get a little closer with nature. I'm not a fan of slugs, but there were some banana slugs, GROSSED me out, no joke. Other than that, it was pretty cool - I got to spend some quality time with some friends. :D



View Mills HS --> Mills Creek Canyon in a larger map

Wednesday, May 5, 2010

Melting Glass [mini-project]

So, glass is bendable, melt-able, and shape-able under the high temperatures of fire. After heating the glass for a long time, I was able to reshape it, using the proper tools and a lot of care.

Some things to avoid/take caution of:
-Don't dip the heat glass into cold water - it'll either shatter the glass, or make it very brittle
-Make sure you have the proper equipment: goggles, metal claw (for holding class), it can get hot and even somewhat dangerous
-If the glass parts DO break, make sure to watch out for the sharp parts at the ends of the glass and be sure to clean up any broken bits

Science:
-to bend the glass tube, you have to heat up the area you wish to bend until it is immensely hot
-a sudden decrease in temperature raises the chance of the glass shattering
-if a warm glass tube is filled quickly with cool water, some steam may be produced

Photocredit: My mom (Tracy Lai)

Monday, April 19, 2010

IProposeWe Make A Volcano

IProposeWe Make Our Own Volcano

Photocredit: My mom (Tracy Lai)
Good materials
Places where you can get them:
-Safeway
-Lucky's
-CVS
-Most stores like aforementioned

Links:
- Discovery Kids: Make a Volcano
- About.com: How to Build a Volcano

Materials:
-Volcano (paper mache, clay, dirt, bottles, bottle)
-a Container for 35 mm film
-Food coloring (red or yellow/optional)
-Vinegar
-Liquid dish washing soap
-Baking soda

Procedure:
1. Gather materials
2. Make a container of some sort (bottle, clay, etc.), this will be your volcano
3. Add two spoonfuls of baking soda into the container
4. Add approximately a spoonful of dish soap
5. For a more realistic appearance, add 5 drops of red and yellow food coloring
6. Add one ounce of vinegar to the container to spark the reaction!

Safety Precautions:
-Never hurts to wear goggles
-Tuck in shirts
-Gloves (optional)

Scientific Principles:
-the vinegar reacts with baking soda
-there is some kind of chemical reaction

Thursday, April 1, 2010

Star Testing

So this Tuesday and Wednesday, we had STAR testing, fun right? Yeah, not really. Especially when our grade was the only one that had to come to school early on Wednesday. I ended up RUSHING to school... It was cool though because Mrs. Lighty was really chill and I had probably one of my most relaxing STAR testing experiences so far. Also, it's springbreak next week - and this week has been going by SO SLOW... I think it's taunting me... whatever doooohhhhhh. I'm really excited for springbreak, even though our schedule is so fun we have star testing AFTER it too! hahah...juskidding Anyway, we have a test tomorrow, and I need to studyyyyyyy and finish my packet, so ttyl and peace out.