Analysis of functional groups in organic chemistry

We must know the basic reactions of various functional group. Keeping this in mind, a summery of important reactions of the alcohol functional group are summerised below .

ALCOHOL ( -C-OH)

1. Evolve brisk effervesence of  hydrogen with a small piece of freshly cut dry sodium 
2. Red colour with ceric ammonium nitrate 
3. Form esters with acids (eg: HCl) , acid chlorides (eg: HOCl) , and acid anhydrides ( eg: CH3COO^-) 
4. Give alkyl halides with hydrogen halide (H-X eg : H-Br ) 
5. Give alkyl halides along with hydrochloric acid gas and POCl₃  with PCl5  or HCl and SO₂
6. On dehydration , give ethers and olefines ( alkenes) 
     

Distinction between primary , secondary and tertiary alcohols 

1. OXIDATON

• Primary alcohol gives aldehydes and then acids having same number of carbon atoms
• Secondary alcohols give ketones having same number of carbon atoms and then acids having lesser number of carbon atoms 
• Tertiary alcohols are oxidised under vigorous conditions to ketones and then acids having lesser number of carbon atoms    

1. LUCAS REAGENT  ( A mixture of concentrated HCl and ZnCl2)

• Tertiary alcohols react immediately 
• Secondary alcohols react within five minutes 
• Primary alcohol do not react at room temperature