EVAPORATING COKE 🍻

Aim: To separate a solute from a solvent in a solution using distillation.

Hypothesis: I think the no-sugar coke will evaporate faster because it has no sugar in it to increase the density.

Equipment: A solution of Coca Cola, conical flask, heatproof mat, a delivery tube, bung, Bunsen burner, tripod, gauze mat, retort stand, boss head, clamp, boiling tube, and three different kinds of Coca Cola. The control variables in this experiment consisted of Coke with no sugar, Diet Coke, and regular Coke.

1. Set up equipment as shown in the following diagram.

2. Add approximately 20 ml of Coca Cola to the boiling tube to be heated above the Bunsen burner.

3. Light the Bunsen burner and turn the air hole to a blue flame. My group used our flame with an orange tip for the best results.

4. Heat the solution until most of the solvent has been evaporated. Turn off your Bunsen burner.

Observations

No Sugar Coke Photos

RESULT

Normal Coke Photos

RESULT

RESULT

Diet Coke Photos

Discussion

Why did the normal coke go green?

It's difficult to tell. The only colourant in Coca Cola is the dark brown caramel flavouring and there was nothing else in the boiling tube that could have affected the results. 

Which coke was the quickest to evaporate, and why?

The normal coke was the quickest.

The theory I believe to be most accurate is the difference in boiling points between the three cokes. The boiling point of high fructose corn syrup is 110°c. The boiling point of acesulfame potassium is 225°c. From this we can conclude that the normal coke evaporated faster because of the lower boiling point of it's sugar content compared to the acesulfame potassium in the Diet and No-Sugar coke.

What could we have done to have conducted a more accurate experiment?

We could have used a thermometer to monitor and record the temperature of the coke to determine what temperature it is at during the boiling process.

We could have measured the volume of liquid left in the condensation tube at the end to determine how much of the solvent evaporated from it's original 20 mL. 

Conclusion

The normal coke evaporated faster than the Diet and No-Sugar Cokes because of the lower boiling point of its sugar content compared to the acesulfame potassium in the Diet and No-Sugar coke. 

We were able to separate the liquid from the Cokes using distillation and therefore our experiment was successful. The no-sugar coke evaporated and condensed 4 minutes and 45 seconds slower in comparison to the normal coke, therefore making my hypothesis incorrect!