Caking of solids in a suspension leads to what challenge during redispersion?

• A. Easy redispersion
• B. Difficulty in redispersion
• C. Faster dissolution
• D. No effect on dosage

Answer: (B)

Caking creates a dense, cohesive sediment that forms a solid mass after settling. This compact cake is hard to break apart because stronger interparticle bonds develop and the liquid drains from the pores, reducing wetted surface area. When you try to redisperse, you must overcome these bonds and dismantle the cake, which typically requires more agitation, time, or the use of dispersing agents. So, the main challenge during redispersion is difficulty in redisperging the settled solids. Flocculated, loosely packed sediments redisperse more readily, unlike a cake. Note that a cake can also slow dissolution due to the reduced surface area and can lead to nonuniform dosing if redispersion is incomplete.