Name _____________________________________________________ Date ____________________ Period ________
Electronegativity and Polarity
1. Using electronegativity values, determine whether a bond between each pair of atoms would be pure (non-polar)
covalent, polar covalent or ionic.
a. Br and Br
∆EN = _______
Bond Type = _________________________
b. C and S
∆EN = _______
Bond Type = _________________________
c. C and Cl
∆EN = _______
Bond Type = _________________________
d. Sr and O
∆EN = _______
Bond Type = _________________________
2. For each pair of bonds, circle the more polar bond, label the partial positive (δ+) and partial negative (δ-) ends and
use an arrow (→) to show the direction of polarity in each bond.
a. C – O and C – N
b. B – O and B – S
c. P – Br and P – Cl
d. B – F and B – I
3. Draw the Lewis structure for SO2.
a. Label the partial positive (δ+) and partial negative (δ-) ends and use an arrow (→) to show polar bonds.
b. How many polar bonds are in SO2? ________ How many non-polar bonds are in SO2? ________
c. Is the molecule polar or non-polar? ____________________
d. If the molecule is polar, use an arrow to indicate the direction of the net dipole.
4. Draw the Lewis structure for PCl3.
a. Label the partial positive (δ+) and partial negative (δ-) ends and use an arrow (→) to show polar bonds.
b. How many polar bonds are in PCl3? ________ How many non-polar bonds are in PCl3? ________
c. Is the molecule polar or non-polar? ____________________
d. If the molecule is polar, use an arrow to indicate the direction of the net dipole.
5. Draw the Lewis structure for CCl4.
a. Label the partial positive (δ+) and partial negative (δ-) ends and use an arrow (→) to show polar bonds.
b. How many polar bonds are in CCl4? ________ How many non-polar bonds are in CCl4? ________
c. Is the molecule polar or non-polar? ____________________
d. If the molecule is polar, use an arrow to indicate the direction of the net dipole.
6. Draw the Lewis structure for CHF3.
a. Label the partial positive (δ+) and partial negative (δ-) ends and use an arrow (→) to show polar bonds.
b. How many polar bonds are in CHF3? ________ How many non-polar bonds are in CHF3? ________
c. Is the molecule polar or non-polar? ____________________
d. If the molecule is polar, use an arrow to indicate the direction of the net dipole.
7. Urea, (NH2)2CO, is used in plastics and fertilizers. It is also the primary nitrogen-containing substance excreted
by humans.
a. Which bonds in the molecule are polar and which are non-polar?
b. Which is the most polar bond in the molecule? Which is the more negative atom of this bond?