What is a theoretical plate?

Identify the correct statements from the following:
$(i)$ Electromeric effect is a permanent effect.
$(ii)$ Hyperconjugation is a temporary effect.
$(iii)$ Fractional distillation is used to separate two liquids from a mixture if the difference in their boiling points is less.
$(iv)$ Different compounds are adsorbed on an adsorbent to different extents.

The fragrance of flowers is due to the presence of some steam-volatile organic compounds. These compounds are known as essential oils. At room temperature,these oils are insoluble in water but are miscible with water vapor. Name the suitable method for the extraction of these oils from flowers.

At what temperature and pressure does a liquid vaporize in steam distillation?

How will you separate a mixture of two organic compounds which have different solubilities in the same solvent?

Using column chromatography,a mixture of two compounds '$A$' and '$B$' was separated. '$A$' eluted first,this indicates '$B$' has