[labrat356]

I don't know if this is a really elementary question, but I never get a clear answer when I ask this...

I would say half the chemicals in the lab are all clumped and impossible to get out of the container. Instead of a powder, there's a few large unbreakable (except by dissolving) balls of reagent.  I usually just hit it against a desk or something and shake it like mad and get a tiny bit to break off. I don't know if this reagent is any good?
Stuff like KCl especially (the balls are so hard that after being in the oven then dessicator, it's still a hard ball I can't break)...

[Johnny010]

KCl is not unlike NaCl...like table salt.

It is an ionic lattice and crystalises well out of a solvent...giving hard 'clumps'. It is to be expected.
If you want smaller crystals, just cool the hot fully saturated KCl(aq) solution much quicker than just leaving it to cool slowly (ie...slam it in to a salf ice bath in a thin beaker to expose as much surface area:volume to the ice as possible).