1) The document describes an experiment to test the properties of lipids using various solvents and coconut oil. 2) The results show that coconut oil is soluble in nonpolar solvents like chloroform and ether, but not polar solvents like water or dilute acid due to its nonpolar nature. 3) Additional tests are described to observe the evaporation rates of different oils and their reactions to heat and chemicals.

1. Activity 5A

2. At the end of this activity, the students are
expected to:
A. Name the components of the lipids,
B. describe the characteristics of lipids, and
C. Discuss the principle in each of the tests
employed for lipids.

3.  Determine solubility of one drop of coconut
oil in 1 ml of the ff. solvents: water, dilute
HCl, dilute NaOH, cold alcohol, hot alcohol,
chloroform, and ether.

4.  Lipids are non-polar organic compounds. The
physical properties of fatty acids, and of
compounds that contain them are largely
determined by the length and degree of
unsaturation of the hydro carbon chain. The
nonpolar hydrocarbon chain accounts for the
poor solubility of fatty acids in water. Solubility
of a substance depends on a simple rule of
thumb “like dissolves like” this statement
indicates that a solute will dissolve best in a
solvent that has a similar chemical structure to
itself. The overall solvation capacity of a solvent
depends primarily on its polarity.

5.  Water- Coconut oil is insoluble in water even at room temp.
since water is a polar solvent it will not dissolve coconut oil
which is nonpolar.
 Dilute HCl- Coconut oil is insoluble in dilute acid (dilute HCl)
even if HCl is a nonpolar inorganic solvent. Coconut oil has
higher molecular weight and when dissolved in dilute acid, it
tends to float.
 Dilute NaOH- Coconut oil is insoluble in dilute alkali (dilute
NaOH). In the solution the coconut oil it tends to form as a white
colloidal matter after the addition of dilute alkali.
 Ethyl alcohol- Like water ethyl alcohol is a polar solvent and will
not dissolve most nonpolar solutes as oil.
 Chloroform- Coconut oil is soluble in chloroform. Oil is a
nonpolar organic compound same as chloroform.
 Ether- Coconut oil is soluble in ether since ether is an organic
nonpolar solvent.

6.  1. Place one drop of the following oils
separately on a piece of bond paper
(preferably substance 16). Make sure the
drops are placed apart from each other.
a. Coconut oil
b. Linseed oil
c. Peanut oil
d. Cod liver oil
e. Olive oil
f. Corn oil

7.  Formation of Translucent Spot

8. FORMATION OF TRANSLUCENT SPOT
 Lipids have a characteristic greasy feel
 When brought in contact with a substance like
paper, it penetrate through it producing a
translucent spot
 Fats are non-volatile
 The spot of grease can never absorb enough heat
to vaporize
 When the liquid is inside the sheet of paper, it
diffracts light – TRANSLUCENT PHENOMENON

9.  Based on our test results, it shows that
peanut oil evaporated 1st, followed by
coconut oil, corn oil, cod liver oil and lastly
linseed oil. It is stated that the difference in
molecular weight and number of double
bonds affect the rate of evaporation of oil.
The longer the fatty acyl chain and the fewer
the double bonds the lower the evaporation
rate. In our test the rate of evaporation was
also affected by the quantity of oil dropped in
the paper.

10. Coconut oil
Linseed oil
Peanut oil

11. Cod liver oil Corn oil
Olive Oil

12.  Each lipid is different with each other, especially with the
number and branching of their carbon chain, the longer
the chain and the more it is branching the longer the time
it evaporates. There is also a factor in the degree of
unsaturation of the lipid. Saturated fatty acids or saturated
fats tend to evaporate a lot longer than unsaturated fat.
Saturated fats are composed of many single carbon bonds
that make the substance less volatile. Unsaturated fats are
composed of one or more double bonds. The double
bonds make the fat more volatile. In other words there are
differences in the evaporation of different kind of oil
because their evaporation rate mainly depends upon their
structural formula. The differences in molecular weight
and number of double bonds therefore affect the rate of
evaporation of oil.

13.  In the test there was no change in the color of
litmus paper (Litmus paper blue and red).
Theoretically the oil should turn into acidic
since it was exposed to an open environment
and thus undergo Rancidity. The result was
maybe due to several factors like the oil used
was not fresh.

14.  In the experiment the oil give a positive result
since coconut oil is a lipid and is composed of
glycerol.
Heat
Oil or fat Glycerol + Fatty acid
CH2OH CH2
CHOH KHSO4
Heat CH + 2H2O
CH2OH
(Glycerol ) CHO (Acrolein)