Ionization energy (Ei) is the amount of energy required to remove an electron from a neutral gaseous atom or gaseous ion. Electrons are attracted to the positively charged nucleus; therefore removing an electron requires energy. The process is endothermic, and so ionization energies have a positive value. The first ionization energy (Ei1) is the energy associated with the removal of an electron from the neutral gaseous atom. The reaction is represented for the generalized atom X as: X rightarrow X^+ +e^-
Based on position in the periodic table and electron configuration, arrange these elements in order of decreasing E Rank the elements from highest to lowest ionization energy.
1. Na
2. F
3. Li
4. N
5. B
6. O
a. Highest ionization energy
b. Lowest ionization energy

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

if it's not useful, feel free to report for mistake in answer.

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.