Chemistry : Organic Chemistry – Some Basic Principles and Techniques

What is the principle of chromatography? Name the important types of chromatography. 
Or
Give a brief description of the principle of chromatography?

Explain the principle of paper chromatography.

How will you detect the presence of carbon and hydrogen in an organic compound ?

Discuss soda lime test for the detection of nitrogen. 

Discuss the chemistry of Lassaigne's test. 

Discuss the Lassaigne's test for the detection of nitrogen. 

How will you detect the presence of sulphur in an organic compound by oxidation test?

How will you detect the presence of sulphur in an organic compound by Lassaigne's test?

Why is it necessary to use acetic acid and not sulphuric acid for acidification of sodium extract for testing sulphur by lead acetate test?