Lenz

__**Putting a candle out using vinegar and calcium carbonate**__

Calcium carbonate Vinegar Big beaker Small beaker Matches Candles Bell jar Stopwatch Spatula Tongs
 * Materials used:**

I used three different set-ups in my experiment.
 * Set-up/Results:**

Set-up 1: In the first set-up, I placed a lighted candle under a bell jar with a beaker of calcium carbonate solution. The aim of the experiment was to extinguish the flame with the carbon dioxide that forms in the reaction between calcium carbonate and vinegar. While the candle flame went out after a little over a minute, I couldn't tell whether it was because of the carbon dioxide smothering the flame or because the candle just exhausted its oxygen supply. Even after I used a stopwatch to time whether it took longer to extinguish the flame with or without the calcium carbonate solution, my results were inconclusive as there was barely any difference between the two times. After this, I decided to change my set-up of the experiment.

Set-up 2: The second set-up was a bit simpler. I used a big beaker, a smaller beaker full of more calcium carbonate solution, a candle and a lighted candle. I placed the candle and the solution within a bigger beaker and tried to put out the flame with the use of carbon dioxide alone. 45 minutes, two bottles of vinegar, and an obscene amount of calcium carbonate later, tragedy struck as my candle tipped over and extinguished itself in the water, ending the experiment illegitimately. It was crushing, but during the post-experiment observations, I realised that I had made a ton of carbon dioxide in the beaker, as a match could be extinguished about a quarter of the way down. I figured that the reason why the candle didn't go out was because the concentration of the carbon dioxide gas was too low, which means that the gas couldn't smother the flame. As a result, I changed my set-up to one that would increase the concentration of the carbon dioxide gas around the candle.

Set-up 3: To do that, I used a smaller beaker, as a smaller surface area would result in a higher concentration. I placed the candle in the beaker, and poured vinegar and calcium carbonate. The candle was put out quickly by the carbon dioxide gas formed from the reaction (CaCO3 + 2 HC2H3O2 ---> Ca(C2H3O2)2 + H2CO3), which proved my hypothesis to be true.

The results I got from this set-up differed greatly from the previous set-up. First of all, I didn't need to use the obscene amount of material I used in the previous set-up. Secondly, the flame went out quickly; in contrast to the 2nd experiment that flickered on multiple occasions in the experiment without going out. One of the things that I found abnormal during the experiment was how the flame didn't seem to go out despite the fact that I had created a whole ton of carbon dioxide. I figured that this had something to do with the concentration of the carbon dioxide across the surface area of the beaker, as the carbon dioxide was too spread out. As a result, the carbon dioxide was not concentrated enough to cut the flame off from it's oxygen supply, which allowed it to stay alive.
 * Post-experiment analysis and experiment observations:**

The science behind the experiment is simple. The flame of a candle burns when fed with oxygen. When the oxygen supply to it is cut off, the flame is extinguished. The goal of the experiment was to see if the gas produced in the reaction between calcium carbonate and vinegar was carbon dioxide, and I figured that if the aforementioned gas could put out a flame, then it had to be carbon dioxide.
 * The Science behind the Experiment:**