1. The pressure on 2.50L of an enclosed gas changes from 105kPa to 40.5kPa. If the temperature remains unchanged
what is the new volume?
2. A gas with a volume of 3.50L at a pressure of 200kPa is
allowed to expand to 14.0L. If the temperature remains
unchanged what is the new pressure?
3. A sample of gas occupies 5.00L at a temperature of 27
degrees celsius. What will its volume be at 127 degrees
celsius if the pressure remains the same?

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.