Respuesta :

Answer: the equation for the reaction is NH4Cl (s) --> NH3 (g) + HCl (g)

equation for heat reaction:

ΔH25° = (ΔH25° NH3 + ΔH25° HCl) - ΔH25° NH4Cl)

question 2:

the 1st and 3rd reactions are better ontained through  refrence sources and the 2nd and 4th are the easiest and safest to measure in the laboratory. The 1st and rd reaction contains noxious gases this is because there is a (g) in both of the reactions. And the 2nd and 4th does NOT contain noxious gases so i assume its the safest to measure out in the lab