You mean similar b.p right ?

 Wurtz reaction with mixed alkyl halides(two different alkyl halides) will lead to all the possible products, for ex. reaction between CH3Br & C2H5Br with sodium metal will give CH3-CH3, C2H5-C2H5, & CH3-C2H5; hence the reaction is not suitable for preparing alkanes with odd no. of carbon atoms.