Which bond is the most polar: C—H, O—H, or H—Cl? For each of these bonds, determine which atom has a partial positive charge.

Strategy Bond polarity depends on the difference in electronegativity between the two bonded atoms. So we can look up the electronegativity values and subtract to find the difference in each case. Negatively charged electrons are drawn more strongly toward an atom with higher electronegativity, so the less electronegative atom has a partial positive charge.