Question 6 Answer

(a) -Add 50 cm3 of the brand orange juice to a concial flask.
-Add 20 cm3 of ethanoic acid to the concial flask.
-Add a few drops of the starch .
-Titrate with iodine solution from burette until the first permanent blue black colour is obtained.
-Repeat experiment twice.
-Record observation and results.

(b) Vitamin C prevents and cure scurvy, acts as an Anti-oxidant in the body, protects against immune system deficiencies, repair all body tissues, wound healing, help maintenance of cartilage, eye disease, even skin wrinkling, and protecting our health.  Lower your cancer risk, Regenerate your vitamin E supplies, Improve iron absorption.

(c) Vitamin C is highly sensitive to air, water and temperature.


About 25% of the vitamin C in vegetables can be lost simply by blanching (boiling or steaming the food for a few minutes).

This same degree of loss occurs in the freezing and unthawing of vegetables and fruits. Cooking of vegetables and fruits for longer periods of time (10-20 minutes) can result in a loss of over one and a half of the total vitamin C content.

When fruits and vegetables are canned and then reheated, only 1/3 of the original vitamin C content may be left.

d.When Vegetables were cooked with both heat and Sodium Hydrogencarbonate, it softened   the plant cells and allowed the vitamin C to seep out of the plants.

Sodium Hydrogencarbonate hastened this process, because the base properties of the Sodium Hydrogencarbonate reacted with the acid properties of the vitamin C, rendering it neutral.

Hence there will be less Vitamin C present in the vegetable.

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