n-Butane on monochlorination under photochemical condition gives an optically active compound "P". "P" on further chlorination gives dichloro compounds. The number of dichloro compounds obtained (ignore stereoisomers) is:

Step-by-step solution

The structure of n-butane is CH₃-CH₂-CH₂-CH₃ . Monochlorination of n-butane gives two structural isomers: 1-chlorobutane and 2-chlorobutane. Among these, 2-chlorobutane ( CH₃-CH₂-C^ * HCl-CH₃ ) contains a chiral carbon atom and is optically active. Thus, the optically active compound "P" is 2-chlorobutane. Further chlorination of 2-chlorobutane can take place at any of the four carbon atoms, yielding the following dichloro compounds (ignoring stereoisomers): 1. Chlorination at C-1: CH₃-CH₂-CHCl-CH₂Cl (1,2-dichlorob