Question

what is the molar solubility of NH4Cl (ammonium chlorine) at 20 degrees celsius? how do u find out?

Answer 1

you can look in solubility tables, there you have solubility of chemicals on certain temperatures, here you go:
http://en.wikipedia.org/wiki/Solubility_table

Answer 2

isn't there a conversion you write? with the moles and molar mass??

Answer 3

when you got the value you can easily convert it to what ever units you want example:
http://www.ehow.com/how_5179123_calculate-solubilities.html