I have read this sentence as an example of the verb "auflösen" usage:
Die Tablette bitte in Wasser auflösen.
Why is it not
Die Tablette bitte im (in dem) Wasser auflösen?
Sorry about this simpleton question, but I thought it's essential to use the articles in order to clarify the case of the nouns as in this case "Dativ".
Perhaps in spoken English it's OK to drop the second article in this example but in Deutsch I'm not sure.