The diagram shows the electron configuration of an atom of an element for the electrons in the s and p orbitals. A shaded circle is shown. There are two concentric circles around this shaded circle. In inner concentric circle has two dark shaded dots. The outer concentric circle has two dark shaded dots in the corresponding position to the inner concentric circle. The outer concentric circle also has five light shaded dots, two on the left and two on the right boundary and one at the bottom.

What is the group number of the element in the periodic table?

17
16
2
1

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

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.