How many grams of water are required to dissolve 27.8g of NH4(NO3)(MM=80.05 g/mol)to make a 0.500M solution?

2 answers

I don't know. The definition of molarity = M is #moles/L of SOLUTION and not grams of water.
This is a verbatim question on my final review for 2nd quarter College General Chemistry and it didn't make any sense to me so that is why I decided to post and ask for assistance. You not knowing either doesn't make me feel any more confident in my ability to pass this class :(