In various chemical processes such as reactions and the dissolving of salts, heat is either absorbed or given off. We call these events either an endothermic (heat in) or exothermic (heat out) process. It is usual to detect these heat events by measuring the temperature change associated with the process. In this problem, you will dissolve several salts in water, measure the resulting temperature change, and then make deductions about the nature of the process.
7. Calculate ΔT (ΔT = TAfter – TBefore) for each mixture and record it below.
ΔT NaCl = ºC
ΔT NaNO3 = ºC
ΔT NaCH3COO = ºC
Which solutions are endothermic and which are exothermic? What is the sign of the change in enthalpy ΔH in each case?