The boiling point of hf is 1. higher than, 2. lower than, 3. similar to the boiling point of h2 , and it is 1. higher than , 2. lower than , 3. similar to the boiling point of n2

The boiling point of HF is 67.1°F and H2 is -423.2°F so HF is HIGHER than H2 and N2 boiling point is -320.4°F so HF is again HIGHER than N2.

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.