Why the gross reading is needed when doing the titration?

The answer is below

Explanation:

Because various factors can affect the actual value of the titration outcome. Some of these factors can range from errors from a researcher also known as human error, misreading the quantities, researcher's perception of the color, or wrong procedure in carrying out the experimentation.

Hence, in order to avoid such error, a researcher needs to be thorough during the process of experimentation, and using gross reading can help to avoid these errors when the titre value is eventually determined.

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.