Choose the substance with the highest viscosity. Explain your answer. A) (CH3CH2)2CO B) C2H4Cl2 C) HOCH2CH2CH2CH2OH D) CF4
The Correct Answer and Explanation is:
The substance with the highest viscosity is C) HOCH2CH2CH2CH2OH (1,4-butanediol).
Viscosity is a measure of a liquid’s resistance to flow, which is influenced by the strength and type of intermolecular forces present in the substance. The stronger the intermolecular forces, the higher the viscosity.
Let’s analyze the given options:
A) (CH3CH2)2CO (Diethyl ketone)
This is a ketone, where the only intermolecular forces are dipole-dipole interactions and van der Waals forces. The dipole-dipole forces are moderately strong, but not as strong as hydrogen bonding.
B) C2H4Cl2 (1,2-dichloroethane)
This is a halogenated hydrocarbon. The primary intermolecular forces are dipole-dipole interactions due to the electronegativity difference between chlorine and carbon. However, halogenated compounds generally have relatively low viscosity compared to those capable of hydrogen bonding.
C) HOCH2CH2CH2CH2OH (1,4-butanediol)
This molecule contains two hydroxyl (OH) groups capable of hydrogen bonding. Hydrogen bonding is a very strong intermolecular force, which leads to higher viscosity. The presence of two OH groups increases the ability to form hydrogen bonds, making 1,4-butanediol much more viscous than other molecules in the list.
D) CF4 (Carbon tetrafluoride)
This molecule is nonpolar, and its primary intermolecular force is London dispersion forces (induced dipole-induced dipole forces), which are weak. As a result, CF4 has a very low viscosity.
Conclusion:
1,4-butanediol (C) has the highest viscosity due to the strong hydrogen bonding between its OH groups. The other substances have weaker intermolecular forces, leading to lower viscosity.
