Ethanol From Sucrose

Purpose

The purpose of this experiment was to make ethanol from sucrose through a fermentation reaction.

Procedure

Refer to handout, “Lab 12: Ethanol from Sucrose”

Results

Table 1: Mass, Volume, Density, Concentration and Percent Yield of Pure Ethanol

Vial Mass of ethanol (g) Volume of ethanol (mL) Density (g/mol) Concentration Percent yield of pure alcohol

1 .344 g .4 mL .86 g/mol 72.5%

2 .429 g .43 mL .99 g/mol 5%

3 .347 g .36 mL .96 g/mol 22.5% 32.3%

Discussion

The weight of the first tared vial was 3.626 grams. The mass of ethanol was .344 grams. The volume of ethanol in the first vial was .4 mL. The density was .86 grams/mol. The concentration was 72.5%. The weight of the second tared vial was 3.599 grams. The mass of

The experiment would have been unsuccessful if there was no ethanol obtained or if there was a very small yield of ethanol such as 5% or lower was obtained.

A practical use for fractional distillation would be for purifying drinking water. Fractional distillation is the separation of a mixture into separate parts or fractions. Fractional distillation can separate the germs, bacteria and any impurities from the water. Once those are removed, the water will now be safe for human consumption.

One way to improve this experiment would be to collect the supernatant with a 0.50 mL syringe instead a 1.0 mL syringe. This way 0.50 mL of supernatant would be collected more accurately. It is a lot easier to collect the wrong amount when using a 1.0 mL syringe. Another way to improve this experiment would be to allow the fermentation reaction to happen for two weeks instead of one week. The longer the reaction can occur, the higher the yield of ethanol will be. The last way to improve this experiment would be to centrifuge the product, using a micro centrifuge. If this step was done then the supernatant would be clear, pure and ready for fractional distillation. Also, if this was done, more ethanol may have been