In the CRW exercise, which material combination is compatible?

In the CRW exercise, which material combination is compatible?

• A. Water and inorganic sulfides
• B. Inorganic sulfides and aldehydes
• C. Inorganic sulfides and inorganic peroxides
• D. Water and aldehydes

Answer: (D)

Compatibility in this context means two materials can come into contact under normal handling without causing a hazardous reaction, excessive heat, gas evolution, or formation of dangerous products. Water is a mild, common solvent that typically doesn’t drive chemical transformations with aldehydes, so aldehydes in water are generally stable and can be mixed or stored together safely under ordinary conditions. That’s why water and aldehydes form a compatible pair: there’s no strong acid–base, redox, or radical process expected between them in normal conditions, and many aldehydes are already handled as aqueous solutions. In contrast, combining water with inorganic sulfides can pose hazards because sulfides can release toxic hydrogen sulfide gas under certain conditions, especially if the environment becomes acidic or oxidizing, making them not compatible. Pairing inorganic sulfides with aldehydes can lead to unwanted sulfur-containing reaction products or other instability. Finally, inorganic sulfides with inorganic peroxides can trigger highly exothermic, dangerous redox reactions, which is clearly incompatible.

Compatibility in this context means two materials can come into contact under normal handling without causing a hazardous reaction, excessive heat, gas evolution, or formation of dangerous products. Water is a mild, common solvent that typically doesn’t drive chemical transformations with aldehydes, so aldehydes in water are generally stable and can be mixed or stored together safely under ordinary conditions.

That’s why water and aldehydes form a compatible pair: there’s no strong acid–base, redox, or radical process expected between them in normal conditions, and many aldehydes are already handled as aqueous solutions.

In contrast, combining water with inorganic sulfides can pose hazards because sulfides can release toxic hydrogen sulfide gas under certain conditions, especially if the environment becomes acidic or oxidizing, making them not compatible. Pairing inorganic sulfides with aldehydes can lead to unwanted sulfur-containing reaction products or other instability. Finally, inorganic sulfides with inorganic peroxides can trigger highly exothermic, dangerous redox reactions, which is clearly incompatible.