In class we completed an experiment in which you create two "worlds" with different levels of CO2, and then examine the effect which it has on the temperature of the "worlds" as time passes.
Independent Variable: Time
Dependent Variable: Temperature of the "world" in °C
Controlled Variables: Concentration of hydrochloric acid, mass of calcium carbonate "chips", volume of distilled water, time left for the observation of the worlds
Independent Variable: Time
Dependent Variable: Temperature of the "world" in °C
Controlled Variables: Concentration of hydrochloric acid, mass of calcium carbonate "chips", volume of distilled water, time left for the observation of the worlds
T h e r e s u l t s
The results above show that even within a small period of time (45 minutes) a difference in the temperatures of the two worlds has appeared. The world with more CO2 has increased more in temperature in comparison to the control. This tiny experiment done on a small scale gives an indication as to what has happened to the world due to the extreme increase in CO2 levels. Although the increase is small, it is significant and supplies evidence that higher CO2 levels do result in temperature increase.
E v a l u a t i o n
From the experiment in class, many improvements could be made in order to make the experiment more reliable. For example, many variables were not controlled in the way of which they should be. The mass of the calcium carbonate was not weighed out but instead judged by the rough estimation in the beaker. Likewise when we measured the volume of water instead of precisely using a measuring cylinder we used a rough guess of what we thought "looked the same". The temperature of the water could have been controlled in order to guarantee a controlled and equal test (this can be the same with the hydrochloric acid). Likewise a better cover for the beakers could have been used rather than cling film as the cling film could have had a small tear in it or perhaps it didn't cover the top fully on one of the beakers. All of these inaccuracies should have been controlled which would have consequently made the results more reliable and valid.