When $$100$$ mL of $$1.0$$ M HCl was mixed with $$100mL$$ of $$1.0$$ M NaOH in an insulated beaker at constant pressure, a temperature increase of $$5.7$$°C was measured for the beaker and its contents (Expt.1). Because the enthalpy of neutralization of a strong acid with a strong base is a constant $$(-57.0$$ kJ $$mol-1)$$, this experiment could be used to measure the calorimeter constant. In a second experiment (Expt$$. $$2), $$100$$ mL of $$2.0$$ M acetic acid (Ka$$ $$=$$ $$2.0$$ × $$10-5) was mixed with $$100mL$$ of $$1.0$$ M NaOH (under$$ identical conditions to $$Expt.1) where a temperature rise of $$5.6$$°C was measured.(Consider$$ heat capacity of all solutions as $$4.2$$ J $$g-1K-1$$ and density of all solutions as $$1.0$$ g $$mL-1$$ Enthalpy of dissociation $$(in$$ kJ $$mol-1) of acetic acid obtained from the Expt. $$2$$ is The pH of the solution after $$Expt.2$$ is

Question

When $$100$$ mL of $$1.0$$ M HCl was mixed with $$100mL$$ of $$1.0$$ M NaOH in an insulated beaker at constant pressure, a temperature increase of $$5.7$$°C was measured for the beaker and its contents (Expt.1). Because the enthalpy of neutralization of a strong acid with a strong base is a constant $$(-57.0$$ kJ $$mol-1)$$, this experiment could be used to measure the calorimeter constant. In a second experiment (Expt$$. $$2), $$100$$ mL of $$2.0$$ M acetic acid (Ka$$ $$=$$ $$2.0$$ × $$10-5) was mixed with $$100mL$$ of $$1.0$$ M NaOH (under$$ identical conditions to $$Expt.1)  where a temperature rise of $$5.6$$°C was measured.(Consider$$ heat capacity of all solutions as $$4.2$$ J $$g-1K-1$$ and density of all solutions as $$1.0$$ g $$mL-1$$ Enthalpy of dissociation $$(in$$ kJ $$mol-1) of acetic acid obtained from the Expt. $$2$$ is  The pH of the solution after $$Expt.2$$ is

Infinity Learn · Accepted Answer

For Expt (1) Q $$=$$ $$msx(+57)$$ For neutralization of $$100m$$ kg of strong acid with strong baseFor $$1$$ gr equivalent of strong acid (vs) strong base; Enthalpy of neutralization is – $$57$$ kg\ Calometric constant $$=$$ $$1$$ kJ. $$k-1For$$ expt (2)100$$ ml of $$2m$$ acetic acid $$(vs) $$100ml$$ of $$1$$ M NaOH is the neutralization $$100$$ meq acetic acid is neturalisation with (or) meq of $$NaOHQ=msX+5.6=1$$×$$5.6kJ/100mlFor$$ $$1000$$ meq → $$56$$ kJ∴ Q $$=$$  Enthalpy of dissociation of acetic acid $$=$$ $$1$$ kJ  In expt $$(2)The$$ final solution is a buffer containing Equimolar of acid and salt∴$$pH=pKa=4.7$$

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