practical

Question 1

What does the iodine solution test test for?

Answer 1

Carbs

Question 2

What does the biuret test test for?

Answer 2

Proteins

Question 3

What does the ethanol emulation test test for?

Answer 3

Fats + Lipids

Question 4

What does the Benedicts solution test for?

Answer 4

Benedicts solution tests for reducing sugars.

Question 5

What apparatus is needed for the iodine solution test?

Answer 5

Iodine Solution, Dropper, and Substance that is being tested

Question 6

What apparatus is needed for the biuret test?

Answer 6

Potassium hydroxide, food, copper sulfate, test tube and dropper

Question 7

Apparatus needed for the ethanol emulsion test

Answer 7

Test tube, substance, water, ethanol

Question 8

What apparatus is needed for the benedicts solution?

Answer 8

Hot water bath, test tube, substance, benedicts solution

Question 9

Method for the iodine solution test?

Answer 9

Apply 1-2 drops of Iodine solution onto a substance. If the substance changes colour from yellow-orange to blue-black it has got carbohydrates inside.

Question 10

Method for Biuret test?

Answer 10

Potassium hydroxide mixed with substance. Two drops of Copper Sulfate then added. If the pale blue mixture turns purple there is protein in the substance.

Question 11

Method for the ethanol emmunision test?

Answer 11

Substance is mixed with ethanol and then shaken. Some of the mixture is poured into water and then is shaken again. Fats + oils dissolved in the ethanol will float to the top, leaving a cloudy layer on the top of fats are present.

Question 12

Method for Benedicts Solution test?

Answer 12

Substance (as solution) is mixed with equal volume benedicts solution, placed in hot water bath for a few minutes. If the solution changes colours there are reducing sugars.

Question 13

Hazards for each test and how to prevent.

Answer 13

Some of the chemicals being handled with can be very corrosive, need to be slow and steady to make sure not to spill any of the substances. Also need to where goggles to make sure that nothing gets into your eyes.

Question 14

Positive and Negative results for the Iodine Solution test

Answer 14

Positive : Potato, as it is a carbohydrate
Negative: Ham, doesn’t have any carbs.

Question 15

Postive and negative result of the Buiret’s test

Answer 15

Positive : Avocado - has lots of protein in
Negative : White bread - Has no protein in.

Question 16

Positive and negative result of the ethanol emmulsion test.

Answer 16

Positive : Butter, has lots of fat + lipids in.
Negative : Broccoli, has no fat in

Question 17

Positive and negative results of the benedicts solution

Answer 17

Positive : Chocolate has many reducing sugars in
Negative : Sweet Potato - even though it has sweet in its name it has no reducing sugars.