Which carbon atom has the most partial positive character?

A carbon atom would have a partial positive character if it is bonded with a much more electronegative element. The periodic trend for electronegativity is increasing as you go from right to left, and decreasing as you go down a group. Thus, a more electronegative element than carbon would either be nitrogen, oxygen and fluorine. Hence, bonds involving CN, CO and CF would have a partial positive character for carbon.

Which metal is less dense