Select all cases where the substance shown has a molecular dipole?
(HO)2SO2 sulfuric acid
CH3CF3 1,1,1-trifluoroethane
C4H8 cyclobutane
OF2 oxygen difluoride
CH3CH2CO2H propionic acid
i know OF2 don't have dipole.
To determine whether a substance has a molecular dipole, you need to analyze the molecular structure and the distribution of polar bonds. A molecular dipole occurs when there is an asymmetrical distribution of electron density in a molecule, resulting in a partial positive charge (+δ) on one side and a partial negative charge (-δ) on the other side.
Let's go through each substance you mentioned to determine if it has a molecular dipole:
1. (HO)2SO2 (sulfuric acid): This compound has multiple polar bonds between oxygen and hydrogen. The sulfur atom also has a double bond with one of the oxygen atoms, but this bond is symmetrical and does not contribute to the overall dipole moment. Overall, (HO)2SO2 has a molecular dipole.
2. CH3CF3 (1,1,1-trifluoroethane): This compound consists of carbon (C) and fluorine (F) atoms. The C-F bonds are polar due to the difference in electronegativity between carbon and fluorine. However, the molecule is symmetrical, and the individual dipole moments cancel each other out. Therefore, CH3CF3 does not have a molecular dipole.
3. C4H8 (cyclobutane): Cyclobutane is a carbon-based compound with only C-H bonds. Carbon and hydrogen have similar electronegativities, resulting in nonpolar bonds. Since there are no polar bonds or an asymmetrical distribution of electron density, cyclobutane does not have a molecular dipole.
4. OF2 (oxygen difluoride): As you correctly mentioned, OF2 does not have a molecular dipole. This is because the molecule is symmetrical, with the same fluorine atoms on both sides, canceling out any dipole moment.
5. CH3CH2CO2H (propionic acid): Propionic acid contains polar bonds between carbon, oxygen, and hydrogen atoms. The structure is asymmetrical due to the presence of the carbonyl group (C=O). These polar bonds result in an overall molecular dipole in propionic acid.
Therefore, the substances with a molecular dipole are (HO)2SO2 (sulfuric acid) and CH3CH2CO2H (propionic acid).