Chem Mini Project 3: Making my own rock candy!!

I don't have to buy rock candy from stores anymore! Since I now know how to make my own rock candy. :)


Materials:

• 1 cup of water
• 3 cups of table sugar or sucrose
• a clean glass jar
• a pencil or a Popsicle stick
• string
• a pan or bowl for boiling water and making solution
• spoon or stirring rod
• a hot plate
• a lifesaver hard candy

How I Made It:

1. Mix the sugar and water together.
   
2. Then put it on a hot plate and turn it on high until the sugar is dissolved into the water.
3. Next, tie the string to the Popsicle stick and the other end of the string through the hole of the lifesaver candy and tie a knot.
4. Pour water onto the hanging string and cover the string with sugar.
5. Pour the sugar water mixture into the small jar.
6. Balance the Popsicle stick on top of the jar and leave the lifesaver candy hanging so that it does not touch the bottom of the jar.
7. Place it somewhere safe and come back after 3-7 days to see the formation of crystals!

Science:
Since water is the universal solvent, many substances can dissolve in it, including sugar. However, at a certain point, a substance cannot dissolve anymore and that is when we know that the solution is saturated. When we heated the water and sugar, we increased the saturation capacity, making it possible for more sugar to dissolve because heat causes molecules to move apart and have more energy.

When we cool the water down, the solution becomes supersaturated, having too much sugar. Since we placed the string in a supersaturated solution, the sugar will be attracted the the already-existing solid molecules stuck to the string, therefore creating crystals. As time passes by, the water will evaporate while the sugar remains in the solution. Because it will become more saturated, more sugar will be added and our crystal will grow bigger and bigger.


Photocredit to Erica Sue 5th period:

Mini Blogpost 2: Dancing Raisins!

Today, I made raisins dance in a cup full of soda.

Materials I used:

• a tall, clear glass or plastic cup
• a few raisins
• a can of clear, colorless soda like 7-up or Sprite
  

Procedure:

1. Pour the can of soda into the clear cup. Watch how the carbon dioxide gas (bubbles) are released from the liquid.
2. Then, drop 6 or 7 raisins into the cup.
3. Watch what happens to the raisins.

Observation: The raisins all sink to the bottom at first but then one by one, they quickly ascend to the top and then just as quickly, they sink to the bottom again.

Science: At first, the raisins sink to the bottom of the cup because raisins are more dense than the liquid. Since it is a carbonated drink, releases bubbles or carbon dioxide. When the raisins stick to some of the bubbles, the raisin starts to float up to the top because of the increase in buoyancy. However, when the raisin reaches the top, the bubbles pop and are released into the air. Since the buoyancy is decreased, the raisin sinks to the bottom again. The raisins float and sink until most of the carbon dioxide gas is gone into the air. As time passes, the raisin gets too heavy to float to the surface.

Chem Standard Blogpost :O

ChemStd 7d: Problems about heat flow involving temperature changes can be solved by using known values of specific heat and latent heat of phase change.

Heat is the energy transferred from one object to another because of a difference in temperature.

No Phase Change Problems:

To solve these kinds of problems, use the equation Q= mcΔT.
m= mass of the matter being measured. (g)
c= specific heat, the amount of heat energy required to raise 1g of a substance 1°C. (cal/g°C) or (J/g°C)
ΔT= change in temperature, the increase or decrease in the temperature of the matter (°C), = final temperature - initial temperature

Q= mcΔT must refer to only ONE object. Mixing your references will result in a wrong answer.

The value of Specific Heat is not the same for all types of matter. Heat affects the temperature of those things with a high specific heat much less than those with a low specific heat. Water has the highest specific heat while metals have low specific heats so a small amount of energy raises the temperature of metals a lot.

Here are Specific Heat Capacities of some common substances:



Water (liquid) - 4.184 J/g°C
Water (ice) - 2.03 J/g°C
Water (steam) - 2.0 J/g°C

To convert to J/g°C, use the Calorie-Joule Conversion: 1 cal = 4.184 J.

For example:

A block of lead having a mass of 20.0 grams is heated from a room temperature of 22.4 ^oC to a temperature of 85.4 ^oC. What would be the added heat to the lead?


From:

http://www.neoam.cc.ok.us/~rjones/Pages/online1014/physics/chapter4/pages/heat.html

1. Write the formula
2. Substitute the variables
3. Simplify the equation and cancel the units.
   
4. Calculate the answer
5. Box your answer and don't forget to include the units!
   

You can also find the value of the other variables by rearranging the equation:

m= Q/cΔT

c= Q/mΔT

ΔT= Q/mc


Latent Heat of Phase Change Problems:

Heat of Fusion - ( ΔHfus) - the heat absorbed by a substance that is melting from a solid state to a liquid state at a constant temperature.

Heat of Solidification - (ΔHsolid) - the heat lost when a liquid changes to a solid at a constant temperature.

Heat of vaporization - (ΔHvap) - the heat absorbed by a substance that is vaporizing from a liquid state to a gaseous state at a constant temperature.

Heat of condensation- (ΔHcon) - the heat lost when a gas changes to a liquid at a constant temperature.

Energy is conserved in all physical and chemical changes:
ΔHfus = -ΔHsolid
ΔHvap = -ΔHcon


Changes of State for Water:
Melting: ΔHfus= 80 cal/g
Solidifiction: ΔHsolid = -80 cal/g
Vaporization: ΔHvap = 540 cal/g
Condensation: ΔHcon = -540 cal/g

To solve phase change problems, use the latent heat of fusion or latent heat of vaporization formulas:

For freezing or melting, use:
Latent Heat of Fusion of Water: Q= mΔHfus
ΔHfus(H2O)= 80 cal/g = 334 J/g

For boiling or condensation, use:
Latent Heat of Vaporization: Q= mΔHvap
ΔHvap(H2O) = 540 cal/g = 2260 J/g

For example:
How many calories are needed to melt 225 g of ice at 0°C to liquid at 0°C?

Step 1: Write the formula
Step 2: Substitute the variables and cancel units.
Step 3: Calculate and box the answer. Don't forget to include the units.

Mills Canyon Park Field Trip :)

Our chemistry class went on a field trip to Mills Canyon Park! I thought I needed some relaxing time so i decided to go on that field trip. However, I thought it was going to be cold there so I wore layers to the hike. But instead of it being windy and cold, it was very very hot there! I was also carrying a very heavy backpack there. So I think I would've enjoyed it more if i had worn less layers and had carried a lighter bag. But I still thought it was really relaxing. I also liked looking at the scenery and observing nature.

Here is a map of the park:


View Mills Canyon in a larger map

Layered Liquids: Oil and Water

Today, I mixed water and oil together and discovered something interesting...

Materials needed to do this experiment:

• 1/4 cup (60 mL) of water
• 1/4 cup (60mL) of oil
• a small glass
• food coloring
  

What I Did:

1. First, I poured the water into the glass
2. I Added a couple of drops of green food coloring and mixed them together.
3. Then I added the oil into the glass.
4. Next, I tightly covered the glass with plastic wrap while holding it on top of the sink( just in case it spills).
5. Shake the glass until both liquids are thoroughly mixed.
   

Results:
It started to bubble. After all the bubbles disappeared, i saw that the layer of oil was on top of the water. In the end, there were still some bubbles on the layer of water but no bubbles on the layer of oil.

Science:
This experiment shows that water and oil are "immiscible" because they do not mix. The reason why the oil is on top of the water is because there is a difference in density of the two liquids. Because the oil is less dense than water, it is on top of the water.

IProposeWe make "fireworks" in a glass! :3

How to create underwater "fireworks".

Materials You Will Need:

• Water
• Oil
• Food Coloring
• Tall Clear Glass
• Another cup or glass
• A Fork

Procedures:

1. Fill the top of the tall clear glass almost full with warm water or water at room temperature.
2. Poor about 1-2 tsp of oil into the other cup or glass.
3. Add a couple of drops of food coloring into the cup or glass of oil.
4. Stir to mix the food coloring and the oil with the fork. Stop after breaking up the food coloring drops into smaller drops. You don't want thoroughly mix the liquid.
5. Pour the oil and food coloring into the tall clear glass.
6. Watch how the food coloring slowly sinks into the glass, with each droplet expanding as it falls, resembling fireworks.

Scientific Principles:

1. Food coloring does not dissolve in oil, it only dissolves in water.
2. When you stir the food coloring in the oil, you break up the coloring droplets.
3. Since water is more dense than oil, the oil floats on top of the glass.
   
4. In step 6, the color diffuses outward as the heavier colored droplets fall to the bottom.
   

Safety Precautions:

• Wash your hands before and after experiment
• Be careful not to get food coloring on your clothes but if you do, use diluted bleach in warm water
  

For more information, go to:
http://chemistry.about.com/od/4thofjulychemistry/a/waterfireworks.htm

Badminton sweatshirts????

So a few days ago we saw the swimming team wear their new sweatshirts.... it looked cool so me and my friends were like: How come we don't have badminton sweatshirts????!!! Then one of my friends suggested we design our own and then ask our coach whether we can actually get the sweatshirts or not. Coach told us that it costs a LOT of money... and the more words you have, the more money it costs... We're not sure if the team would want to buy sweatshirts but even if they don't... i would :). We were thinking of a slogan and what to put on the sweatshirts. Crystal Springs had a nice slogan: Don't hate the player, hate the game. I think we're deciding between the slogans: "As bad as it gets", or something about not giving up points for the game, which our coach said to us yesterday. Today during lunch, my friend drew an AMAZING picture for our sweatshirts and it looks SO COOL! In the front, there's the word Badminton but the B is made from two birdies. Its really creative ;) i can never make anything like that >.>..

Game at South City High

Our second game at South City was a bummer... I was really happy when we won at our first game against Crystal Springs. Our returning players told us that South City is considered our rival since every year that we play them, the scores are always really close and are usually 1 game off. Last year, they beat us 7-8. So this year, many of the ranked players were nervous because they wouldn't want to mess up their game. When we arrived at South City, i thought their gym was HUGE! It was also really blue... and the lighting was kinda horrible. You couldn't even see the birdie because it blended in with the lighting. So it was extremely hard to play... mayb thats why lots of schools lose to them :O. But anyways, it was my first game away from home so i was able to see the gyms of other schools. They had AUTOMATIC bleachers!!! and they were SO high... they almost reached up to the ceiling. Our coach later told us that our gyms will be getting remodeled next year but i won't be able to see it because it'll be done by the year 2013 :(. They even had like 8 courts! Most schools only had 7.... i feel so poor xD.

David Webb

So yesterday in chem, we had a guest speaker come to our class to talk to us about gases and vacuums. At first, i thought it would be really boring and i was not looking forward to it. However, during lunch, my friend told me that last year, the people in olson's class thought that David Webb was really interesting and that he wasn't boring at all. When i got to chem class, i found that all the desks were moved so that they were all facing the lab tables. Then i noticed that two of the lab tables were full of small little things. While David Webb was teaching us about all the different things that vacuums and gases do, he also demonstrated it through various experiments. I thought that this was a really good way to teach because i have to see the experiment in order to learn it.

There was this one experiment where there were two metal half circles. After he put the two circles into the vacuum, they were shut tightly together. Then Mr. Olson showed us a picture of a lot of horses pulling on that circle. I think that means that it takes a lot of power to get those two half circle things separated.

I had to leave early for a badminton game but later on, my friend told me that i missed a marshmellow experiment ;(

1st Badminton Game :3

So i'm glad i was able to join the badminton team and all but.... the coach is REALLY strict.... One of the days of the first week, a group of teammates were about like 5 minutes late to practice and she closed the door on them. She tells us that she absolutely HATES tardiness. It's also really weird and scary how she yells at me about something every other day. But i see her do that to other people on the team too so I feel better :). I'm sure i'll get used to her yelling sooner or later.

Oh! on our first badminton game against Crystal Springs... we won! so now our record is 1-0. :) I was surprised that the actual game ended be4 our normal practice times did. While we were warming up, we all gathered together in front of our coach and she was looking at us like Why aren't you guys warming up like i told you to?? and then someone brought in the cake which we all pitched in to buy for her. I could tell she was really surprised about it because her face was all red and she was blushing :3! awwww i've never seen her like that before!

After we won the game, we went to the Lenai and we ate the cake!! it was really tasty. When everyone got a cake already, there were two extra pieces so these two guys from the team said hmmm we should cake her.. and she heard it and she was like NOOO thats not funny guys! I have to coach after this!!! So then they chased her to the girls lockerroom and she hid there for like a minute. Then they were waiting right outside the door for her and a group of people gathered around to watch, including me :D. And then when she finally came out, stating that its not funnyyy, they caked her!!! it was SO FUNNY. haha she even got cake on her hairr. I was surprised that she wasnt pissed at us... In the end we had to clean it up but i thought it was worth it. :D

Strange Weather o.o

The weather has been so weird lately. Its February and i think its supposed to start warming up by now but there's been a LOT of rain. Last week, i was walking home and it started showering! When i was a block away from my front door, i saw the sun and it felt kind of warm. I think it's been mostly sunny in the afternoon and cold/ rainy in the morning.

Today at school we had a rally! It was pretty awesome except for the fact that my idiot teacher didn't tell our class which rally we were supposed to go to and so when i figured out i was actually the first rally, there was no more seats left on the bleechers and my friend and i had to sit on the floor. Actually, my friend told me to sit on the bleechers, a spot right in front of him but since i was with another friend, i didn't want to leave her. It all worked out in the end because my other friend came and swooped into the seat. :P

OMG the quad game against Burlingame is today! but i can only stay until 6:30 because i have yucky tutoring to go to >.> Then at 7:30, the WINTER OLYMPICS start! I can't wait to watch that :D

Can't wait for February 14!

This year's February 14 is so special!
It's not only the day of Valentine's Day but it is also Chinese New Year AND my friend's birthday!
Its very strange and funny now that I think about it.
But my friend dislikes this because she says that people are just going to give her money for Chinese New Year and that will include her birthday presents. xD
I also kind of don't like the fact that her birthday is so close to chinese new year because since my dad is back in the US, i can't hang out with friends as much because I have to spend time with him and will probably have to skip her birthday celebration :(.

But oh well its only this year anyways. Strange day :D

Valentine's day activity for Price's AS english :)

So in my english class, my classmates decided they wanted to do something special for valentine's day. <3>.> and i didn't have time to get him another present so in the end, i just gave him the chocolate with a mini teddy bear and a few keychains :) Not sure if he likes his present but....

I liked the present I got. It was a super cute stuffed animal :) It was a very very VERY cute dog. xD

A day off on 2/5

so for some reason, everyone gets a day off of school on February 5th. I think its because all the teachers have to meet together and grade the Cahsee essays. I feel so bad for the teachers :( while us kids are having fun, they're working. Well anyway, my math tutor found out that we didn't have school that day and decided to make our tutoring time EARLIER!. I was very disappointed by his decision because i wanted to go play badminton with my friends at Bay Badminton Center (BBC)! :( but oh well. my tutoring started at 9:30 and ended at 10:30 but right afterwards, i rushed to play with my friends.
When i got there, i was shocked to see that half of the courts were closed off because they were repainting it! I also saw many people from Mills playing there and it took a long time to get a court to play. But in the end i had a lot of fun :)

After playing badminton and eating lunch with my friends, i went to see my dad because he had recently come from Hong Kong to visit us :). I don't like how he visits us in the middle of the school year though. But oh well i'm just glad he's here.

CAHSEE exams :(

So my english teacher was very worried about all the sophomores who were taking the CAHSEE exams. A few months ago, the district made us take a practice of the practice test. Then, a few months atfterwards, they made us take it again and that was the official practice test. Then all sophomores had to go to school at 8 am while everyone else slept in until like 11 or 12. I wasn't really scared about flunking this exit exam but i was really annoyed that we had to wake up so early in the morning when i could be sleeping like a baby. <.< style="color: rgb(51, 102, 255);">
But i think i did my essay wrong.... it was such a stupid essay topic!

Horrible Week of 1/19

This week i have a lot of homework/quizzes/tests/projects.
For History, we had to do this propaganda poster analysis thing and it is very confusing and annoying because the instructions were vague.
For 2nd period i will have a test on Paradise Lost which was very hard because i kept on spacing out when we were discussing it in class.
3rd period is even more painful because ive always beeen really bad at math so i never understand new things and i have a quiz on friday.
4th period is my favorite period because its PE! and we dont have hw
5th period i have to finish the packets and study for the test on friday which i dont understand ANYTHING. so i have to study all night long.
6th period i didnt do my hw and didnt turn it in on saturday b/c i didnt know it was due on satuday night at 11:59. And my friend told me on sunday and by then it was already to late.


I am so ready for the weekend

Like Dissolves Like

Dissolving is the process of making a solution by mixing liquids together. In a solution, there are two parts: the solute and the solvent. Solute + Solvent = Solution.

"Like Dissolves Like" means a solvent dissolves solutes with polarities that are similar to their own. Nonpolar solvents dissolve nonpolar solutes.

Break went by WAY too fast

I just got back to school on tuesday even though it was supposed to be on monday but since the teachers have a work day, students get one extra day off. Hurray! :) During the break i didn't get to go anywhere outside of the bay area because my sister had to take SAT classes so i couldnt go to Tahoe like i originally planned to. Oh wells! my friends and i went to play badminton and we hung out. I also went to watch fireworks with my friends at downtown SF but it was SO CROWDED! and it was mostly college people so you see a lot of drunk people walking around and a lot of smoking. I think i inhaled so much smoke i'm probably going to get cancer very very soon. :P And now i'm back in school and the teachers are torturing us to death. :(