Thanks Dr. Courtney for your insight. Yes I need a stronger endothermic reaction. I was hoping to reformulate ammonium nitrate as it is safe for consumers (sealed in a thick poly bag) and a low cost material but I will look into other materials as well.
I'm working on a new invention that requires a disposable instant ice pack using ammonium nitrate and water. I need the temperature of this new ice pack to get within the range of -15 deg F
I have tried using larger quantities of ammonium nitrate but was only able to lower the temperature 6-8...