ammonium chloride?

Question

when ammonium chloride dissolves in a beaker of water, the beaker becomes cold to touch. Please explain this phenomenon.

Answer 1

The reaction is Endothermic.
It forms Hydrochloric acid and ammonium hydroxide by the following process :-
NH4Cl + H2O = HCl + NH4(OH)

The HCl acid produced is very dilute. The ammonium hydroxide formed is about some 5 to 7 degrees celcius.

Answer 2

Lancenigo di Villorba (TV), Italy

YOUR REMARKS
You put several spoons of ammonium chloride in an amount of water standing in a glass beaker, hence you mix it by means of a glass rod or a magnetic anchor. You may note a diminution of
mixture's temperature.
WHY THAT? Temperature falls down because ammonium chloride have two different energy's bonds depending on it stands as crystal form or its aqueous solutions. Since the latter is LOWER THAN the former one, the process needs energy supply. This is a common example of ENDOTHERMIC PHENOMENON.

THERMODYNAMICS FUNDAMENTS
At the endings of XIX century, an american physician (J. W. Gibbs) began an imponent study on the evolutions of many chemical phenomena. He developed a new themodynamics property, a VERY POWERFUL tool involved in correlations and predictions of many and many physico-chemical events. I tell about "H that is Enthalpy", a thermodynamics potential as "E that is Inner Energy" it is.
At the time, the scientists stated the "First Principle of Thermodynamics" among its applications there is the case of "thermodynamics systems" maintaining their "E" since they cannot exchange energy in its usual forms, e.g. heat and mechanical work. Developing this result, Gibbs stated that any REVERSIBLE PROCESSES have "H" 's changes determined by its mass transfers when it is led in ISOBARIC and ADIABATIC conditions. More completely, he could describe differential of "H" as it have a writing interesting changes of main physico-chemical variables, e.g. pressure, entropy and molar amounts of reaction's actors.

WHAT IT HAPPENS?
In your experiment, I may assume you get DILUTE SOLUTIONS that are it run a REVERSIBLE PROCESS (e.g. few salt in water leads to small irreversibilities). In this manner, I assume that there will be not any changes of pressure, there will be not any heat exchanges. Hence, the "H" 's differential is not depending on pressure or entropy (e.g. reversible hypotheses). On the other hand, the solutions is built by adding salt to water. Hence, I evaluate the "Energy's Bonds that is Specific Enthalpy" of ammonium chloride in crystal form and the "energy's bonds" of 1 M aqueous solution of the same compound. The literature report the former state of ammonium chloride having a GREATER energy's bond THAN ammonium solution's one. Finally, in the differential writing I find an algebraic negative difference which is similar to the "thermal capacity measured at constant pressure". Since the latter quantity is related to temperature changes of the solution, I shown why temperature falls down.

I hope this helps you.

Answer 3

The energy required to break apart the (NH4)+ and Cl- ions is greater than the energy released when these ions become hydrated, so the overall process is endothermic.

Answer 4

I think it creates a reaction that is.... endothermic.. meaning it draws energy in and makes the surroundings colder..

Answer 5

3 NH4Cl + Na3PO4 ---> 3 NH3 + H3PO4 +3 NaCl You have to balance both sides

Answer 6

it undergoes an endothermic reaction.