CHEM 219
Lab Report & Lab Notes
Experiment #: 4 Fermentation
Portage Learning
Inside you will get:
- Clear, Concise Scientific Language.
- All Tables and Figures Labelled Clearly.
- Included Units for All Measurements.
- Proofread Report.
- Portage Learning.
, Chemistry Lab Report
Experiment #: 4
Title: Fermentation
Purpose:
Explore the topic of organic synthesis by performing a fermentation of
sucrose to ethanol.
Procedure:
1. Add half a packet of dry yeast (3.5 grams) to the beaker and cover it in
50 mL of distilled water.
2. Use a glass stir rod to gently stir the mixture and grind the yeast to
break open the yeast cells and release some of the enzymes
3. Add 0.35g of sodium phosphate and continue mixing.
4. While yeast begins to release its enzymes, add 51.5 grams of sugar
(sucrose) and 150 mL of water. Stir with a glass rod to dissolve the
sugar. Add small amounts of water as needed to help the sugar
dissolve.
5. Slowly pour the sugar water into the fermentation flask (not all), add
the yeast mixture into the flask, then use the rest of the sugar water
to wash the beaker with yeast to ensure we get all of it and add the
rest to the flask.
6. Protect the fermentation from excess oxygen and dust by
placing a rubber stopper onto the flask and seal it well.
7. Add a solution of lime water to the test tube which acts as a soft seal (gas trap).
8. After a week fermentation will cease because the production of CO2 will stop.
9. Add 10g of sea light (filtering aid that sticks to cellular debris from yeast
and keeps it from clogging the pores of the filter paper) to the mixture
and gently mix.
10. Put a filter paper into the buchner funnel and turn on the water
aspirator. Use distilled water to wet the surface of the filter paper and
push it down to initiate the suction. Pour the solution through to filter it.
11. Fractionally distillate the crude ethanol mixture and collect a total
volume of 100mL of distillate which will be used to determine the
density of the solution which will allow us to determine the amount
of ethanol produced.
12. Add a hydrometer to the liquid and measure where the meniscus meets
the scale and record the mass
13. Perform the flame test with the original distillate sample and the
fermented distillate. The fermented distillate should catch fire.
14. Perform iodoform test. Add a small quantity of the substance to be
tested to a test tube. Control is distilled water. Add a solution of
iodoform (iodine dissolved in a saturated solution of potassium iodide).
Add a small quantity of 1 molar of sodium hydroxide to each tube and
shake. Heat the tubes in a warm water bath. While tubes are heating
add an additional small quantity of iodoform.
lab-4-notes-pdf/
Lab Report & Lab Notes
Experiment #: 4 Fermentation
Portage Learning
Inside you will get:
- Clear, Concise Scientific Language.
- All Tables and Figures Labelled Clearly.
- Included Units for All Measurements.
- Proofread Report.
- Portage Learning.
, Chemistry Lab Report
Experiment #: 4
Title: Fermentation
Purpose:
Explore the topic of organic synthesis by performing a fermentation of
sucrose to ethanol.
Procedure:
1. Add half a packet of dry yeast (3.5 grams) to the beaker and cover it in
50 mL of distilled water.
2. Use a glass stir rod to gently stir the mixture and grind the yeast to
break open the yeast cells and release some of the enzymes
3. Add 0.35g of sodium phosphate and continue mixing.
4. While yeast begins to release its enzymes, add 51.5 grams of sugar
(sucrose) and 150 mL of water. Stir with a glass rod to dissolve the
sugar. Add small amounts of water as needed to help the sugar
dissolve.
5. Slowly pour the sugar water into the fermentation flask (not all), add
the yeast mixture into the flask, then use the rest of the sugar water
to wash the beaker with yeast to ensure we get all of it and add the
rest to the flask.
6. Protect the fermentation from excess oxygen and dust by
placing a rubber stopper onto the flask and seal it well.
7. Add a solution of lime water to the test tube which acts as a soft seal (gas trap).
8. After a week fermentation will cease because the production of CO2 will stop.
9. Add 10g of sea light (filtering aid that sticks to cellular debris from yeast
and keeps it from clogging the pores of the filter paper) to the mixture
and gently mix.
10. Put a filter paper into the buchner funnel and turn on the water
aspirator. Use distilled water to wet the surface of the filter paper and
push it down to initiate the suction. Pour the solution through to filter it.
11. Fractionally distillate the crude ethanol mixture and collect a total
volume of 100mL of distillate which will be used to determine the
density of the solution which will allow us to determine the amount
of ethanol produced.
12. Add a hydrometer to the liquid and measure where the meniscus meets
the scale and record the mass
13. Perform the flame test with the original distillate sample and the
fermented distillate. The fermented distillate should catch fire.
14. Perform iodoform test. Add a small quantity of the substance to be
tested to a test tube. Control is distilled water. Add a solution of
iodoform (iodine dissolved in a saturated solution of potassium iodide).
Add a small quantity of 1 molar of sodium hydroxide to each tube and
shake. Heat the tubes in a warm water bath. While tubes are heating
add an additional small quantity of iodoform.
lab-4-notes-pdf/
