Which student is determining the atomic mass of sodium (Na)? A.
Cheryl finds the average mass of sodium isotopes found in nature
B.
Abu counts the number of neutrons in an isotope of sodium
C.
Maria adds the number of protons to the number of neutrons in sodium atoms
D.
Jerry counts the number of protons in sodium atoms found in nature

im pretty sure its b

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.

answerambulatory;