Question

Chemically volatile oils differ from fixed oils in one of the following characters:

• A. Mixtures of eleoptenes adn steroptenes
• B. Presence offlavonoids
• C. Presence of plant acids
• D. Hydrophilic in nature

Answer 1

The Correct Option is A

Chemically volatile oils are distinct from fixed oils in their composition and behavior. The question here focuses on identifying the characteristic that differentiates volatile oils from fixed oils.

Volatile oils, also known as essential oils, are primarily composed of a mixture of two classes of compounds: eleoptenes and steroptenes.

1. Eleoptenes: These are the liquid constituents of volatile oils. They are usually responsible for the fragrance and volatile nature of these oils.
2. Steroptenes: These are the solid constituents of volatile oils. They crystallize out from the oil when it is cooled.

For fixed oils, they are triglycerides and are non-volatile, mainly composed of long chain fatty acids. This composition is entirely different from that of volatile oils.

Let's critically analyze the options given:

• Mixtures of eleoptenes and steroptenes: This option correctly identifies the characteristic mixture found in volatile oils.
• Presence of flavonoids: Flavonoids are a class of plant secondary metabolites that are not primarily present in volatile oils.
• Presence of plant acids: While plant acids can be part of both volatile and fixed oils in small amounts, they are not characteristic of volatile oils.
• Hydrophilic in nature: Volatile oils are generally hydrophobic, which means they do not mix well with water. This is the opposite of being hydrophilic.

Thus, the correct answer is that chemically volatile oils differ from fixed oils in being mixtures of eleoptenes and steroptenes.