JEE Advanced 2015 Paper 2

Paragraph for next 2 Questions When 100 mL of 1.0 M HCl was mixed with 100 mL of 1.0 M NaOH in an insulated beaker at constant pressure, a temperature increase of $5.7^{\circ}\mathrm{C}$ 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 ($-57.0\ \text{kJ mol}^{-1}$), this experiment could be used to measure the calorimeter constant. In a second experiment (Expt. 2), 100 mL of $2.0\ \text{M}$ acetic acid ($Ka = 2.0 \times 10^{-5}$) was mixed with 100 mL of 1.0 M NaOH (under identical conditions to Expt. 1) where a temperature rise of $5.6^{\circ}\mathrm{C}$ was measured. (Consider heat capacity of all solutions as $4.2\ \mathrm{J\ g^{-1}\ K^{-1}}$ and density of all solutions as $1.0\;\mathrm{g\ mL}^{-1}$)