Draw VSEPR sketches for each compound below. Then, indicate whether the each of the following compounds is polar or nonpolar by drawing molecular dipole moments when appropriate.
CHCl3
CH2Cl2
CCl4
H2O
CH3CH2CH2CH2CH3
The correct answer and explanation is :
Here are the VSEPR sketches and polarity for each of the compounds you mentioned, with an explanation:
- CHCl3 (Chloroform):
- VSEPR Geometry: Tetrahedral
- Bond Angles: ~109.5°
- Polarity: Polar. The molecule has a central carbon bonded to three chlorine atoms and one hydrogen atom. The chlorine atoms are more electronegative than carbon and hydrogen, creating a net dipole moment toward the chlorine atoms. The asymmetry in the molecular shape causes an overall dipole moment.
- CH2Cl2 (Dichloromethane):
- VSEPR Geometry: Tetrahedral
- Bond Angles: ~109.5°
- Polarity: Polar. This molecule also has a tetrahedral shape, with two chlorine atoms and two hydrogen atoms. The difference in electronegativity between chlorine and hydrogen results in partial negative charges on chlorine and partial positive charges on hydrogen. The molecule is asymmetrical, giving it a net dipole moment.
- CCl4 (Carbon Tetrachloride):
- VSEPR Geometry: Tetrahedral
- Bond Angles: ~109.5°
- Polarity: Nonpolar. Though the C-Cl bonds are polar, the molecule is symmetrical. The individual dipoles cancel each other out, resulting in no overall dipole moment.
- H2O (Water):
- VSEPR Geometry: Bent (Angular)
- Bond Angles: ~104.5°
- Polarity: Polar. Water has a bent molecular shape, with oxygen being more electronegative than hydrogen. This results in a significant dipole moment, as the electron density is pulled toward the oxygen atom, creating a net dipole pointing from the hydrogen side to the oxygen side.
- CH3CH2CH2CH2CH3 (Pentane):
- VSEPR Geometry: Linear for each C-C bond, overall tetrahedral around each carbon
- Bond Angles: ~109.5° around each C
- Polarity: Nonpolar. Pentane is a straight-chain alkane, and the C-H bonds are generally nonpolar. The molecule is symmetrical with no significant dipole moment.
The dipoles are shown in the sketch where appropriate, with arrows pointing from the more positive region to the more negative region.