Question 12.3: 

Write bond life fourmulas for: Isopropyl alcohol, 2,3--Dimethyl butanal , Heptan-4-one.

The bond line formulae of the given compounds are:
(a) Isopropyl alcohol       
                                                      H     OH      H
         |       |         |
HCCCH
         |                |
        H              H
                                               
(b) 2, 3–dimethyl butanal
                                       CH3    CH3   O
               |          |       ||
H3CCHChCH
                     
                 
(c) Heptan–4–one
                            
                                                                  O
                                        ||
H3CCH2CH2CCH2CH2CH2