To transform electrical energy into mechanical energy, the electromagnet in a motor must rotate in just one direction. What allows this consistent rotation
to occur?
O A. The terminals of the battery frequently switch polarity.
O B. The electric current in the loop of wire frequently reverses
direction.
O C. The commutator frequently causes the loop of wire to turn.
O D. The poles of the permanent magnets frequently switch places.
SUBMIT

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.