The atom with the same number of neutrons as 12c is 9be. 11b. 13c. 14n.

Answer : The atom with the same number of neutrons as is,

Explanation :

Atomic mass number = 12

Atomic number = 6

Atomic number = Number of protons = Number of electrons = 6

Number of neutrons = Atomic mass number - Atomic number = 12 - 6 = 6

Now we have to determine the number of neutrons in the given options.

Atomic mass number = 9

Atomic number = 4

Atomic number = Number of protons = Number of electrons = 4

Number of neutrons = Atomic mass number - Atomic number = 9 - 4 = 5

Atomic mass number = 11

Atomic number = 5

Atomic number = Number of protons = Number of electrons = 5

Number of neutrons = Atomic mass number - Atomic number = 11 - 5 = 6

Atomic mass number = 13

Atomic number = 6

Atomic number = Number of protons = Number of electrons = 6

Number of neutrons = Atomic mass number - Atomic number = 13 - 6 = 7

Atomic mass number = 14

Atomic number = 7

Atomic number = Number of protons = Number of electrons = 7

Number of neutrons = Atomic mass number - Atomic number = 14 - 7 = 7

Therefore, the atom with the same number of neutrons as is,

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.