Creating our own little "Earth".

As I said in my previous blog posts, we’re studying ecology at the moment in Bio HL IB. The other day, having a lesson about the same topic than in my last blog post (The correlation between CO2 levels and global temperature), we carried out a really simple experiment with the aim of showing us that this correlation can actually exist in a much smaller level if he have three things: Carbon dioxide, a sealed mini-atmosphere and a source of light.

The experiment consisted in the following steps:

-You take two flasks.

-Cover the base with a thing layer of water.

-Put a thermometer in each flask.

-in a side of one of the flasks, we fill a conic flask with Calcium Carbonate (CaCO3) and we seal the top of the conic flask connecting a tube from it to the nearest flask.

-We cover both Flasks with a plastic layer, leaving a space for the thermometers and the tube in one of the flask that is connected to the conic flask. 

-We uncover the conic flask and we pour hydrochloric acid. Immediately after that, we seal the conic flask again, which is connected to the other flask.

-We put both flasks under a source of light like a lamp, arranging them in a way that both get the same amount of light.

So what do we expect to happen?

Both flasks should have the same initial temperature, 21ºC in my case, but when they are heated by the light, the one that is connected to the conic flask should become hotter, because CaCO3 reacts with Hydrochloric acid forming CO2 (Which will pass through the tube), CaCl2 and H2O (Which will remain in the conic flask). As we end up having more CO2 in one flask than in the other one, we should end up with more temperature in the flask with extra CO2.

And this actually was what happened, after 30 minutes, the normal flask ended up having 30ºC and the one with extra CO2 ended up having 32ºC. It may not look as a big difference, but we have to take in count a lot of factors. Although the Extra-CO2 flask should had a bigger temperature because the CO2 traps heat and doesn’t let it get out of the flask, there wasn’t a lot of time for this to happen. Also, it will loose a bit of heat because the room was at a much lower temperature. The water would also have an effect, as it has a high specific heat (Amount of energy needed to heat or cool down an object), but it is needed because it makes much easier to measure the temperature with the thermometers… And even with all this factors, the CO2 was able to rise the temperature 2 centigrades! This shows us how CO2 levels have and incredible effect in global temperature and how they are absolutely linked together.