Volatile Oils

Step 1: Understanding the oil composition.
Cymbopogan flexuosus, also known as lemongrass, is a plant known for its essential oil, which is rich in citral. Citral is a mixture of two isomers, geranial and neral, and gives the oil its characteristic lemon-like fragrance.
Step 2: Analyzing the options.
(A) Citral: Correct — The oil from Cymbopogan flexuosus is rich in citral, making it an important compound used in perfumery and aromatherapy.
(B) Alpha-Terpienol: This compound is typically found in other essential oils, not in Cymbopogan flexuosus.
(C) Alpha pinene: Alpha pinene is found in pine and other coniferous trees, not in lemongrass oil.
(D) Nerol: Nerol is a compound found in some essential oils but is not a major component of Cymbopogan flexuosus.
Step 3: Conclusion.
The correct answer is (A) Citral as it is the primary component of Cymbopogan flexuosus oil.

Step 1: Understanding castor oil.
Castor oil is a non-volatile oil that is derived from the seeds of the castor bean plant (*Ricinus communis*). It is considered a fixed oil, meaning it does not evaporate like volatile oils.
Step 2: Analyzing the options.
(A) Volatile oil: Volatile oils, such as essential oils, evaporate easily and are not fixed oils. Castor oil is not a volatile oil.
(B) Wax: This is incorrect, as castor oil is not a wax.
(C) Oleo-resin: Oleo-resins are a mixture of oil and resin, which does not apply to castor oil.
(D) Fixed oil: Correct — Castor oil is a fixed oil, meaning it is not volatile and remains stable at room temperature.
Step 3: Conclusion.
The correct answer is (D) Fixed oil as castor oil is a fixed, non-volatile oil.