1. Grind the sugar into a powder. (Longman dictionary)
2. lumps of chalk crushed to (a) fine white powder (Oxford dictionary)
Which does 'a powder' in sentence 1 and 2 mean, a pile of powder or a kind of powder or both?
And I wonder if 'a powder' can be changed into 'powder' in sentence 1.
If it's possible, is there any difference in the meaning?
Crushing or grinding something to powder, or to a powder, mean the same thing.