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Enthalpy of change determination

In an experiment to determine the enthalpy change (△H) for the neutralisation reactionNaOH(aq) + HCl(aq) NaCl(aq) + H2O(l)100 mL (VHCl) of a 0.5 M (CHCl) HCl solution are reacted with 100 mL (VNaOH) of a 0.5 M (CNaOH) NaOH solution.
The initial temperature of the system (Ti) is 20.1°C, whereas the final temperature (Tf) is 23.4°C.
Assume that the density (p) of both 0.5 M HCl and 0.5 M NaOH solutions is 1.0 g mL-1, and that the specific heat capacity (Cp) is 4.183 J g-1 K-1.
a) Calculate the amount of heat in J (i.e. the enthalpy change △H) involved in the reaction, stating whether it is endothermic or exothermic.
b) Calculate the molar enthalpy in kJ mol-1 (Hm) for the reaction.
Original post by gm18
In an experiment to determine the enthalpy change (△H) for the neutralisation reactionNaOH(aq) + HCl(aq) NaCl(aq) + H2O(l)100 mL (VHCl) of a 0.5 M (CHCl) HCl solution are reacted with 100 mL (VNaOH) of a 0.5 M (CNaOH) NaOH solution.
The initial temperature of the system (Ti) is 20.1°C, whereas the final temperature (Tf) is 23.4°C.
Assume that the density (p) of both 0.5 M HCl and 0.5 M NaOH solutions is 1.0 g mL-1, and that the specific heat capacity (Cp) is 4.183 J g-1 K-1.
a) Calculate the amount of heat in J (i.e. the enthalpy change △H) involved in the reaction, stating whether it is endothermic or exothermic.
b) Calculate the molar enthalpy in kJ mol-1 (Hm) for the reaction.


Use Q=-mc(d)t
where m is the mass, c =4.183 Jg^-1k^-1, and dt the change in temp.

Then use △H = Q / n
where n is the moles used.

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