Which has more mass? a
1 mole of Carbon
b
1 mole of Oxygen
c
1 mole of Chlorine
d
1 mole of Hydrogen

Explanation:

12.00 g C-12 = 1 mol C-12 atoms = 6.022 × 1023 atoms

 The number of particles in 1 mole is called Avogadro’s Number (6.0221421 x 1023).

6.022 ×1023 atoms

1 mol or     1 mol

6.022 ×1023 atoms

clouds form

solid ice forms on leaves.

water droplets form on grass.

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.