Which molecule is not polar (possesses no net dipole)?
Option 1. acetone [Marvin structure]
Option 2. cis-dichloroethene [Marvin structure]
Option 3. methylbromide [Marvin structure]
Option 4. trans-dichloroethene [Marvin structure]
Option 5. dibromomethane [Marvin structure]
I am not familiar with the Marvin structures; however, I believe the only non-polar molecule listed is the trans-dichloroethene.
That was right! Thank you!
To determine which molecule is not polar, we need to identify the molecule that possesses no net dipole. A molecule is nonpolar if it has a symmetrical shape or if the polar bonds within the molecule cancel each other out.
To determine the polarity of a molecule, we can consider the electronegativity difference between the atoms within the molecule. If the electronegativity difference is significant, the molecule will have polar bonds.
Now, let's analyze the options one by one:
1. Acetone (CH3COCH3): Acetone contains polar bonds between carbon and oxygen, but due to its symmetrical structure, the dipole moments cancel each other out. Therefore, acetone is a nonpolar molecule.
2. cis-Dichloroethene (C2H2Cl2): This molecule has a non-symmetrical structure, and the chlorine atoms have a higher electronegativity than carbon and hydrogen. Therefore, the chlorine-carbon bonds are polar. Additionally, the molecule does not possess any symmetry to cancel out the dipole moments. Therefore, cis-dichloroethene is a polar molecule.
3. Methylbromide (CH3Br): In this molecule, the carbon-bromine bond is polar due to the electronegativity difference between carbon and bromine. However, the molecule does not possess any symmetry to cancel out the dipole moments. Therefore, methylbromide is a polar molecule.
4. trans-Dichloroethene (C2H2Cl2): Similar to cis-dichloroethene, trans-dichloroethene has polar bonds between carbon and chlorine. However, the molecule does possess a symmetrical structure, with the chlorine atoms positioned on different sides of the double bond. As a result, the dipole moments cancel each other out, and trans-dichloroethene is a nonpolar molecule.
5. Dibromomethane (CH2Br2): Dibromomethane has polar carbon-bromine bonds due to the electronegativity difference. However, the molecule does not possess any symmetry to cancel out the dipole moments. Therefore, dibromomethane is a polar molecule.
Based on the analysis, the molecule that is not polar (possesses no net dipole) is option 4: trans-dichloroethene.