What is the relationship between the concentration of particles in a solution and the solution's vapor pressure?

Describe the relationship between a solution's vapor pressure and the number of particles the solute makes in a solution. The decrease in a solution's vapor pressure is proportional to the number of particles the solute makes in a solution.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.