25. Chemical equations should be balanced so that they demonstrate the Law of Conservation of Mass. Which statement about balanced chemical equations is correct?
A
The products must contain the same number and types of atoms as the reactants.
B. The products must contain the same arrangement of atoms as found in the reactants,
C. The products must contain the same number but not the same types of atoms as the reactants.
D. The products must contain the same types but not the same numbers of atoms as the reactants,

a

Explanation:

they have to have the same numbers on each side.

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.