P9. TEST BIURET

OBJECTIVES:
1) Observe the amount of protein that each ingredient has.

MATERIAL:

• Baker 250mL (x5)
• H2O
• NaOH
• CuCO4
• Test tubes (x5)
• MILK with different fat content: full-cream, skimmed milk and soymilk
• egg yolk 
• yolk

PROCEDURES:

We put 100ml of destillated water in all of the beakers

1. in the first beaker we put 10ml of milk
2. in the second beaker we put 10ml of skimmed milk
3. in the third beaker we put 10ml of Soymilk
4. in the four beaker we put 10ml of the yolk
5. in the last beaker we put 10ml of the egg yolk

When we have all of the proteins inside the beaker we need to remove the 

We take 2ml of the 5 diferents dissolution and we put this 2ml inside the test tube

Add 2ml of the NaOH to 20% 

Add 5 drops to the CuCo4 al 1% 

RESULTS:

• Milk: the second aliment have more proteins

• milk skimmed: no proteins

• milk soja: no proteins

• egg yolk: the first aliment to have more proteins

• yolk: have proteins

L8. SAPONIFICATION

OBJECTIVES:
1) Understand saponification reaction
2) Produce soap

MATERIAL:

• 600mL beaker
• Glass Rod
• Goggles
• Gloves
• Clock Glass
• Spatula
• Bunsen Burner
• NaOH
• Water
• Oil
• Essences

PROCEDURES:

We do this experiment with 3 different measures:

Big measures: 

·         In first place take a Erlenmeyer (250ml)

·         We need to weight the necessary NaOH and water

·         When we have the weight we need to remove with a riding rod

·         Then we put the dissolution inside the Erlenmeyer

·         And we put inside the Erlenmeyer 500ml of oil

·         And we removed again

·         And finally we add the essence ( its not necessary)

·         And we put the soap in a suplement

Normal measures

·         In first place we take a beaker

·         In second place we need to do the dissolution of NaOH and water

o   First we take a wach glass and then we go to the electronic balance

o   We measuring 50g of NaOH

o   In second place we put 80ml of distillated water and the 50g of NaOH inside the beaker.

o   In third place we remove and when the dissolution are ready we also take 50ml of the dissolution

·         We take another beaker with the 50ml of the solutions and then we put inside the solution 50ml of oil

·         And we need to remove again

·         When we see the differents capes the soap are ready

·         We put the soap inside the supplement

·         We need to wait 2 or 3 days

Small measures:

·         In first place we take a test rack tube with 2 test tub

·         We go to the electronic balance.

·         We take a wach glass and we put the wach glass in the electronic balance

·         Dissolution with NaOH and water:

o    Very carfully we put 20g of  caustic sosa in the whach glass

o   After we put 80ml of distillated and 20g of sosa caustic in a beaker of 250ml and we removing the solution carfully and slowly

o   When the beaker are hot and the solution are okey

·         We take the pipet and we measured 2ml of this solution (NaOH+Water)

·         And we put this 2ml inside the two test tube

·         And  we put 2ml of oil

·         And we need to remove again

·         And finally we take a beaker and we put the two test tube inside the beaker.

·          And we put the beaker in the Bunsen burner (Water Bath)

RESULTS:

We made soap. 

QUESTIONS:

• What is soap? Solid or liquid substance that, mixed with water, serves for washing. It is obtained from the combination of an alkali with the acids of the oil or another fatty body.

• What reaction has been made?

FATTY ACIDS + ALKALINE SOLUTION = SOAP + GLYCERIN

• What layers have been produced? the soap and the glycerin

L7.LIPIDS PROPERTIES

OBJECTIVES:
1) Test the solubility of lipids.
2) Identify lipids in liquids compounds.
3) Understand what are an emulsion and the effect of detergents.

MATERIAL:

• test tubes

• 250mL beaker

• Water

• Test tube rack

• Cellulose paper

• Dropper

• Scissors

• Glass rod

• Oil

• Soap (detergent)

• ether

• ethanol

• sudan III

• MILK with different fat content: full-cream, skimmed milk and soymilk.

PROCEDURES:

SOLUBILITY OF SOME LIPIDS

1. Clean and dry three test tubes. Label as W (water), ethanol (E) and PE (ether).
2. Add 3 drops of oleic acid to 3 small test tubes.
3. Add 1mL of water in in the first test tube (W)
4. Add 1mL of ethanol in the second test tube (E)
5. Add 1mL of ether in the third test tube (PE)
6. Shake carefully each test tube

LIPIDS IDENTIFICATION:

TRANSLUCENT MARK

7. Cut two piece of cellulose paper.
8. Put 1 drop of water in the first squared piece. 
9. Put 1 drop of oil in the second squared piece. 

SUDAN III DYE

10. In first place take the W test tube of the first experiment and add 2 drops of Sudan III.
11. After  took another 4 test tube( with different fat content)

o   In first test tube one type of milk full-cream

o   In the second tube another type of milk skimmed

o   In the third tube another type of milk soya milk

o   In the last test tube we put soda (S) 

o   And finally add 2 drops of Sudan III in each of 4 test tube and observe the results.

   

    EMULSION AND EFFECT OF DETERGENT

    In first place we need to take a 250ml beaker and put 100ml of water. 

    Add 1ml of olive oil. With a glass rod stir the mixture vigorously and let it stand for a few minutes.

    Observe and make note of what is happening.

    Finally we added 2 drops of soap and stir the mixture again. Let it stand for a few minutes and notice the differences between both mixtures.

RESULTS:

WATER+OIL-> NO SOLUBLE

ETER+OIL   -> SOLUBLE

PE+ OIL-> SOLUBLE

SKIMMED MILK: The solution stain soft orange

Semi-skimmed milk: The solution stain medium orange

Soymilk: It doesn’t change the colour.

WATER AND OIL FORM A TEMPORARY EMULSION

    WATER , SOAP AND OIL FORM A PERMANENT EMULSION

QUESTIONS:

    From your observation, which compounds can dissolve lipids?   As we have obvserved in the experiment, ethanol can dissolve oleic acid

    Do the oil and water mix? What can you conclude about the polarity of the oil if you know that water is polar?   Water and oil can't mix together because water can't dissolve lipids. Oil is a non-polar compound.
Why is liquid the olive oil lat room temperature?   Because it's an insaturated acid and has a low melting point.
Why does a lipid leave a translucent spot on paper?   Beacause it's a fatty acid.
Which type of milk contains more lipids? Why?   Full-cream milk contains more lipids than the others because is fattier.Did the oil and water mix when you added the soap?   Yes

L6. STARCH

OBJECTIVES:
check whether the following substances carried starch


MATERIAL:

• test tubes

• ethanol

• leaf

• H2O

• frankfurt

• jam

• potatoe

• pipette

PROCEDURES:

1. Boil a leaf in water for two minutes.

1. Put the leaf in a test-tube with ethyl alcohol and boil it again for ten minutes.

1. Rinse the leaf with water.

1. Dye the leaf with iodine

 - FRANKFURT, POTATO, JAM

1. Cut them in two halves.

1. Dye them with iodine and put every half in a glass watch.

RESULTS:

it have starch in all ingredients

QUESTIONS:

• Which is the origin of the starch that you can see in the leaf?

• Explain the significance of boiling the leaf in the water?

• Explain the significance of boiling the leaf in ethanol?

• Explain the significance os rising the leaf in water?