A) co2 is non polar while h2o is polar why?
b) why pcl5 is very reactive?
c) h2o is a liquid h2s is a gas. why?

it is a 3 mark question so (a) carries 1 mark, (b)carries 1 and (c)carries 1 mark
following this method and post the question

Due to the man laculay or make up of each substance one liquid when gas molecules are separated from each to calls wonder become opposit of the other the purpose of the bipolar and the non polar is due to his transition of his total Make up.

the increase of protons   hope this

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.