Wednesday, June 16, 2010

The Last Post

Wow, the experiment is over, all my work is handed in, and I suppose this is my last post on my SRP. So, I actually did learn stuff about boiling point elevation and i've already discussed the purpose of the experiment and what the results showed. Something I forgot to mention on my blog was that I learnt something else new! It's called the v'ant Hoff factor and it played a really big role in my experiment. It is the dissociation factor. In my experiment there was salt- an electrolyte, sugar- a non- electrolyte and baking soda- which became an electrolyte when added to water. The fact that salt and bicarb soda were electrolytes meant that it was expected that they would have higher v'ant Hoff factor and therefore, the boiling point elevation was expected to be higher for them. I already discussed vapour pressure and how it influenced the outcome but even before going into vapour pressure- the intermolecular forces played a big role.
So, a few weeks ago, I didn't even know what vapour pressure was and now the SRP is done and over.

oh btw, did you get the pun in the title? hahahaha, i thought it was very punny :)
OMG THE VIDEO UPLOAD WORKED!! TO YOUTUBE THOUGH- SO HERES THE LINK
THIS IS HOW I CARRIED OUT MY EXPERIMENT, it's only the beginning because I couldnt upload for more than 10 mins worth of video but you get the gist of it.:

http://www.youtube.com/watch?v=9z6otvOLpho

SUMMING UP

seeing as this video is taking forever to upload, i might as well finish the rest of this off noww....

SO:

The purpose of this whole experiment was to investigate how the gradual addition of non-volatile solutes affects the boiling point of water. Based on background research, I found that what was supposed to happen was that the addition of non-volatile solutes to boiling water will cause the temperature of the water to rise and boil at higher temperatures because of intermolecular forces, dissociation and vapour pressure. Salt, sugar and sodium bicarbonate were added in 20g intervals to boiling water and the highest temperature reading was recorded at each interval. The results show that each solute raised the boiling point temperature of the water. In the experiment, the independent variable is the amount of solute added to the water. The dependent variable is the temperature of the water. I controlled the variables but because of the subjective nature of determining the boiling temperature at a given time, I came across a few errors where the magnitude of the measured increases deviated from the predictions. However, in total, the experiment supported the common hypothesis that the addition of any non-volatile solute to water increases its boiling point.


The experimental results

These pretty much showed the rise in temperature each time- it all agreed with the hypothesis- the water displacement because of evaporation and the percentage in temperature increases.

So after a very long and tiring experiment, I can conclude confidently, that the addition of various non-volatile chemicals to the boiling point of water will cause the temperature of water to rise and boil at higher temeperatures. The results showed that the addition of salt, sugar or sodium bicarbonate to water increased its boiling point temperature. This is in agreement with the common hypothesis that the addition of any non-volatile solute to water increases its boiling point. However, because of the limited capability of the experimental equipment, the magnitude of the measured increases deviated from the predictions.

Raw results + some observations explained






























ok so i made some observations in all 3 experiments that i recorded in each of the raw results that as soon as I added the solute to the boiling water, the temperature would immediately decrease and then begin to rise again. My explanation for this is that when the solute is added to boiling water, it obviously has a much lower temperature than the water originally so before it begins to dissolve and dissociate etc... its low temperature causes the water temperature to quickly drop but as soon as it begins to dissolve, the water starts to rise again.
Another important observation that I made was that in each experiment, I could actually see water vapour rising and condensing around the place- like when i looked over the pot, i could feel water droplets on my face so there was a lot of evaporation.
In the baking soda experiment- I actually observed in each trial- there was a big reaction with the water. There was a lot of fizzing and bubbles and spilling over the edge of the pot- I actually have a video of that but it isnt working in this blogger upload!!! Anyway, I've linked this to the production of carbon dioxide gas.

upppdate

I HAVE BEEN SITTING HERE FOR 2 HOURS TRYING TO UPLOAD A VIDEO BUT ITS NOT WORKING!!!!!!!!!!!!!!!!!!!!!!! SO ILL PUT IN MY RAW RESULTS...

Tuesday, June 15, 2010

Update 2

This is how the experiment was set up on the hot plate. At the front is the digital thermometer connected to the thermocouple and into the solution.

These are the 20g measurements of salt. It was the same for sugar and sodium bicarbonate. This is the scale that I used to weigh the water before and after and to measure out the different amount of solutes.This is how I cooled the experiment down at the end before I weighed the solution.

Update

OK, WOW I HAVE NEARLY FINISHED THE REPORT!!! IM TRYING TO ADD THE INTERMOLECULAR FORCES OR WHATEVER INTO IT AND THEN EDIT AND MAKE SURE ITS ALL GOOD AND FIX UP ANY STUFF AND THATS IT! FINISHED. I'm trying to upload all the photos and videos now but its really slow- but I will wait...for now.

Thursday, June 10, 2010

DEAR BLOG,

HI BLOG,
I actually have FINISHED doing the experiments! No, I didn't forget to record everything here- it's all in video form and I will add all the videos as soon as possible. I also took photos so I'll post t hem up too.

Sooooo, I did the Salt experiment 5 times- which took forever!!!!!! Seriously, I sat and watched water boil for like 5 hours. I also did the sugar and baking soda 3 times which also took suppppperrrrr long. I didnt record the baking soda on video because it was taking a long time to boil but I do have the first attempt of it where the water totally came out of the top of the pot and I had to stop because it was going everywhere. Sooo I'll post them up soon too.

Right now, I am almost finished the full report so I want to complete that and then I will definately come back here and add all the things-i cant believe it but I actually do get stuff!!

LIKE what the boiling point actually is- IT IS NOT JUST WHEN THE WATER BOILS? NO! It's when the vapour pressure of the solution reaches an equilibrium with the surrounding atmospheric pressure so I get why when you add a non-volatile solute, the temperature rises because it has a vapour pressure of zero so when you add it to the solvent, the solution has the same vapour pressure as the solvent and because of the dilution from the solute, more kinetic energy of the molecules is needed for the solution's vapour pressure to reach the surrounding atmospheric pressure so it boils at a higher temperature. AND YOU WOULD NOT BELIEVE THAT I DIDNT EVEN LOOK AT ANYTHING WHILE I WROTE THAT? I WROTE IT ALL OFF THE TOP OF MY HEAD!! So, it took me ages to get that but I get it now....so now i will finish the report and add everything later.

Friday, June 4, 2010

Experiment Method changes

I did some research and I've found that for every 1 litre of water, the boiling point increases by 1.024 degrees Celsius for every 58.43 grams of sodium chloride (table salt). In this case, it means that for me to even see that there is a change occurring in the experiment, there is no way that 5 gram intervals is going to be enough. Therefore, what I am going to do is say that I will add salt in 20g or more intervals, 5 times which according to this formula should mean that for 100g of sodium chloride added, the boiling point of the water should increase by approximately 1.75 degrees Celsius.
I am reconsidering the quantities that I am going to add at the moment so that the experiment will work properly. I'm going to use the same method and do the experiment sometime in the next few days.
First, I want to find out- cause ok, its reallllyyyyyy complicated but very basically the boiling point elevation describes how the boiling point of a liquid (solvent) in this case, it's water will be higher when another compound is added to it. That means that a solution has a higher boiling point than a pure solvent but this depends on the volatility of a solute so this happens when a NON-VOLATILE SOLUTE (the salt) is added to a pure solvent (water)- and i looked up what that meant and it means "The state of being volatile The state of having a low boiling point and evaporating readily"- thankyou wiktionary :)
SO to rephrase that, when a non-volatile solute is added to a pure solvent, the boiling point of the the solution after the other compound is added to it, will elevate.
This is pretty much the simplest way I can explain it right now...but that's what the experiment is for SO i will do more research on this andddd i feel smarter already :D

Wednesday, May 12, 2010

Climate Graph

PLAN:

Aim: To find how the gradual addition of salt affects the boiling point of water,
and furthermore to find out how different solutes affect the boiling point of water.

Hypothesis: The addition of solutes to boiling water will cause the temperature of the water to rise and boil at higher temperatures.

Method:
1. One litre of water was boiled on the stove.
2. The highest temperature of the boiling water was recorded, using a thermometer.
3. 5 grams of salt was measured on the accurate scale (c. 1 d.p).
4. The salt was added to the boiling water and the solution was stirred.
5. The temperature of the solution of the boiling water and salt was measured and the highest temperature reading was recorded.
6. Steps 3-5 were repeated 3 times, progressively recording results.
7. Steps 1-6 were repeated, replacing salt with sugar and then bicarbonate soda.
8. Steps 1-7 were repeated 5 times.

Tuesday, May 11, 2010

SRP planning

ok, so i've been thinking about it. I have decided that I might do- instead of just how salt affects water, it will be how different compounds e.g. salt, sugar, baking soda and maybe others- im in the process of working it out. I will do the experiment at home and i've done some research and it shows that generally, they should raise the boiling point of water but for some reason, baking soda seems to decrease the temperature. I am interested in finding out why. I'll do some more research and post the method for my SRP soon.

Friday, April 16, 2010

Correction: new project

This is definitely the project I want to do. What I have now decided to do is explore how salt affects the boiling point of water. I was thinking i would do the experiment in a lab and am looking into it because i wanted to use a Bunsen burner, beakers etc.. or if not i would do the experiment in a pot on the stove and when the water reaches boiling point, i would see how the addition of salt, by gradually adding it after it has reached boiling point affects the temperature of the water. The independent variable is amount of salt added. I'll be controlling time and the dependent variable is temperature.
I have designed the experiment so i will measure the amount of salt initially so I make sure each time I add salt, it will be the same amount. After the water reaches boiling point (check with a thermometer), I will add salt, watch the thermometer as the temperature changes... recording results etc... and when I'm finished,I should have a set of results relating temperature of water to addition of salt. I will conduct the experiment several times to make sure it's right. Hopefully, it will all go well :D

Wednesday, March 10, 2010

I think it's the one

I think I am going to do the experiment on the strength of different metal wires and I've got the okay. Roughly, what I've decided to do is get 50cm lengths of different wires, e.g. copper, steel, aluminium and zinc and I will hang them all up at the same place. I will then add weights to each of the wires and measure the expansion for each to determine which metal has the least expansion and is the strongest. I will repeat the experiment 3 times and show expansion as a function of weight (line graph). I think that this is very useful information as wires are used a lot to bear mechanical loads. The independent variable in this experiment is weight and the dependent variable is expansion. All the materials that I need are easy to get and I think it should be a reliable experiment.

Tuesday, March 9, 2010

some ideas

Ok so I did have a few ideas. One plan was to do the expansion of different metals when heated but I can't do that one because the expansion is too small to be measured. The independent variable there is the heat and expansion is the dependent variable.

I thought about a few other ideas too and did a bit of research. I wanted to build a solar powered fan and I did the research and it's possible but it is not the best thing to do because it's a bit difficult but it would make a good long-term project so I'm thinking about it. It wouldn't be an experiment but it would be the developing of the actual fan and building it. I think that would be fun but I would like to do an experiment. The materials for that experiment are a bit dangerous, like a soldering iron so that's another negative. Also, there are not really variables because it isn't an experiment.

I found another experiment I could do. It is
to observe the effect of light on plants. The independent variable is amount of light received. The dependent variable is growth of plant. I think that this idea is fairly common though.

Another idea is how plants grow, as in, the direction that they grow in, relative to where the light is from. The independent variable is where the light is from and the dependent variable is what direction the plant grows in. However, again, I think that this idea is fairly common.

Thursday, March 4, 2010

KEEPING THIS BLOG ACTIVE

I AM KEEPING THIS BLOG VERY ACTIVE.
see here's another post. i think i deserve full marks for that section :D
yeah so i thought about it a bit more and I think I can do the experiment testing strength of different metal wires.
I'll get some wires made of different metals, all of the same length and some little weights and then ill add the same amount of weights to each type of metal wire and see which snaps first and I can probably time how long it takes too if that's necessary. i like the metal expansion one too but I'm not sure if I can do that one. Will seee.....

some ideas... (first post)

i checked my email and i see that i was supposed to post a first post so this is my first post.
ok well, i should post something so im going to do that now...
well, i HAVE been thinking about what to do. my first idea to make happy pills was rejected (thanks Miss Zhang) but yeah...i have a few ideas. I've been thinking about doing maybe expansion of different metals when heated or strength of different wires (like different metals). i think im going to do the second one if i can.