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Molecular Polarity. Topic 4.2. Molecular Polarity. The polarity of a bond depends on the electronegativity differences between the two atoms. The polarity of a molecule depends on: The polar bonds that the molecule contains The shape of the molecule. Molecular Polarity.
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Molecular Polarity Topic 4.2
Molecular Polarity • The polarity of a bond depends on the electronegativity differences between the two atoms. • The polarity of a molecule depends on: • The polar bonds that the molecule contains • The shape of the molecule
Molecular Polarity • If the bonds are of equal polarity and are arranged symmetrically with respect to each other, their dipoles will oppose each other and will cancel each other. In these cases the molecule will be non-polar, despite the fact that it contains polar bonds. • The following molecules are all non-polar because their dipoles cancel out.
Molecular Polarity • However, if the molecule contains bonds of different polarity, or its bonds are not symmetrically arranged, then the polarities will not cancel out and the molecule will be polar. • The following molecules are polar because the dipoles do not cancel out.
Molecular Polarity • Exercise- predict whether the following molecules are polar or non-polar a. PH3 b. CF4 c. HCN
Molecular Polarity • http://www.tutor-pages.com/Chemistry/Molecular_Geometry/Polar_Or_Nonpolar.html