Dear little one,
Have you ever seen how powdered things like flour, sugar or cocoa can get stuck together and form lumps? This is the same thing as caking in chemical engineering!
When certain substances are stored or transported as powders, sometimes they stick together and form solid masses or "cakes". These "cakes" are hard to use, measure or mix properly, which can cause a lot of problems for us grown-ups who use these substances in factories or labs.
Sometimes, the powders in question have a lot of moisture, which makes them clump together more easily. Other times, the particles in the powder can stick together due to static electricity or chemical interactions. In order to prevent caking, scientists and engineers use different methods such as blending the powder with other dry substances, adding anti-caking agents, or changing storage conditions, such as temperature and humidity.
In summary, caking is when powdered substances stick together and form solid masses, which can cause problems when they need to be used. This can be prevented by using special techniques and additives to keep the powder dry and free-flowing.
I hope this helps you understand caking in chemical engineering, my little friend!