Describe in short about the paper chromatography.

Paper chromatography is a method used to distinguish or separate coloured substance mixtures.

In the image, take an example of colured chemical placed in a glass beaker. If a paper is placed in that chemical, coloured spots are separated and displayed on the chromatogram.

It was founded in 1944 A.D by a scientist called Erwin Cargaff.

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.

i believe the answer is 5,000