Ethylene glycol is a commonly used car antifreeze agent. Calculate the minimum amount of ethylene glycol that must be added to 3 kg of pure water in order to prevent freezing of the mixture for temperatures down to 244.3 K. Also calculate the boiling point of this mixture. The molar heat of melting of ice is 6.01 kJ/mol, and the molar heat of vaporization of water is 40.65 kJ/mol.

the answer is d. 74.02

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.