I have read about is dissolving 1 part NH4Cl and 1 part NaNO3 in 1-2 parts H2O Another reaction I read about is the reaction Ba(OH)2.8H2O(s) + NH4NO3(s) Ba(NO3)2(aq) + 2NH3(aq) + 10H2O(l) I want to know how to make this work with only 5mL of space in a closed container. Maybe you can think of another reaction that would work. The reactants cannot be heated and must be able to occur at home without any additional lab.