http://www.ck12.org Chapter 3. Chemical Interactions
arranged. This is illustrated in theFigure3.15. In both molecules, the oxygen atoms attract electrons more strongly
than the carbon or hydrogen atoms do, so both molecules have polar bonds. However, only formaldehyde is a polar
compound. Carbon dioxide is nonpolar.
FIGURE 3.15
Q:Why is carbon dioxide nonpolar?
A:The symmetrical arrangement of atoms in carbon dioxide results in opposites sides of the molecule having the
same charge.
Summary
- In polar covalent bonds, electrons are not shared equally between the two atoms, so one atom is slightly
negative in charge and one is slightly positive in charge. In nonpolar covalent bonds, electrons are shared
equally so the atoms remain neutral in charge. - Covalent compounds with polar bonds may be polar or nonpolar, depending on their arrangement of atoms.
Vocabulary
- polar: Having oppositely charged ends, as in polar covalent bond or polar covalent compound.
- nonpolar: Not having oppositely charged ends, as in nonpolar covalent bond or nonpolar covalent compound.
Explore More
Watch the video about polarity of molecules at the following URL, and then answer the questions below.
http://www.youtube.com/watch?v=LKAjTE7B2x0
MEDIA
Click image to the left for use the URL below.
URL: http://www.ck12.org/flx/render/embeddedobject/53702- When does a polar covalent bond always produce a polar covalent compound?