ANS:D - None of these

An undesirable characteristic for the solvent used in gas absorption is: High gas solubility. Here's why:

• Gas absorption is a process in which a gas is absorbed into a liquid solvent. The goal is typically to remove or recover specific components from the gas stream.
• A solvent with high gas solubility would absorb large quantities of the gas, which could lead to difficulties in separating the absorbed gas from the solvent during subsequent processing steps.
• High gas solubility can result in a high concentration of absorbed gas in the solvent, which may require additional steps such as stripping or regeneration to recover the gas and regenerate the solvent for reuse.
• Solvents with lower gas solubility are often preferred for gas absorption processes because they allow for easier separation of the absorbed gas from the solvent, reducing the energy and cost associated with downstream processing.
• Low vapor pressure and low viscosity are not necessarily undesirable characteristics for the solvent used in gas absorption. Low vapor pressure helps prevent solvent loss through vaporization, while low viscosity can facilitate mass transfer and mixing within the absorption system.