Alex, Andy, Ashton, Ella, Matt, Michael, Rosie and Pete

Purpose: To test if the accumulating CO2 layer is putting out the flame of the candles.

Equipment: Birthday candles, wooden blocks, 20 gallon fish tank, tap water, trash bag, wooden frame to fit fish tank, matches, meter stick graduated in mm, fire, black background to videotape, and video camera.

Procedure: First, we setup our water containment with a garbage bag and a rectangular wooden frame. Then we filled with water. Next we placed the blocks in the container stacking them varying heights depending on the trial. The number with the letter B next to it signifies the height in block lengths (1B is one block high, 2B is two blocks high and so fourth). The value in centimeters after the colon signifies how far from the edge that each stack of blocks was.

Block Arrangement:
1B: 15cm
2B: 25.5cm
3B: 39 cm
4B: 52 cm
Tank: 76.5 cm.

Next, we melted the wax on the bottom of each candle and stuck them onto the wooden blocks. After that, we lit each candle as quickly as possible and placed the fish tank over the candles into the water to make a seal.

While the candles were burning we videotaped the candles going out. We took 7 seven trials.

Once we were finished we divided up the videos among the class and wrote down all observations on the videos we could make. Including the times it took for the candles to go out. We also calculated the time between each candle going out.
After recording all of the data onto one page we compared each test.

Below are pictures of the set up for the experiment and a table containing the results we got.

Figure 1. The wooden frame built to keep water in, to create airtight seal between the the tank and the ground.
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Figure 2. The plastic bag covering the wooden frame before water is poured on it.

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Figure 3. The blocks arranged in height order, ready to have candles placed and lit. The tank completely covered these blocks.


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Figure 4. The experiment completely setup with tank and all.



Data and Analysis:

Trial
Time (sec)
Height Rank
1 Low --> 4 High
Lateral rank
1 Left --> 4 Right
1
307
4
1
1
451
1
4
1
463
2
3
1
505
3
2
2
233
4
1
2
369
2
3
2
408
1
4
2
443
3
2
3
358
3
2
3
377
2
3
3
386
4
1
3
390
1
4
4
226
4
1
4
379
4
2
4
460
2
3
4
466
2
4
5
295
4
1
5
396
1
2
5
458
3
3
5
541
2
4
6
228
4
1
6
379
4
2
6
460
2
3
6
466
2
4
7
255
1
1
7
259
1
2
7
301
1
3
7
388
1

Table 1

In general, the highest candle (at 4B) went out first, however, in trial three as depicted in table three, the second highest candle (at 3B) went out first. Also in all trials except for one the leftmost candle was first to go out. Additionally, in four out of seven trials, there was a longer gap of time from the 2nd and 3rd candles going out than the 3rd and candles going out. It should also be noted that candles didn’t always go out in order from left to right or front to back. The two aforementioned trends suggest that the descending CO2 layer was not putting the candles out because if it was the cause the candles should have gone out in order of height. A reasonable assumption of the cause, that could be gained from our data, is that the CO2 put out the highest candle, but the rest of the candles were put out by the oxygen in the tank being used up.

Conclusion: It is clear through an analysis of our data that the reason for the candles being put out was not strictly the CO2 layer.