A closed vessel with rigid walls contains 1 mol of $${}_{92}^{238}U$$ and 1 mol of air at 298 K. Considering complete decay of $${}_{92}^{238}U$$ to $${}_{82}^{206}Pb$$, the ratio of the final pressure to the initial pressure of the system at 298 K is

The molar conductivity of a solution of a weak acid HX (0.01 M) is 10 times smaller than the molar conductivity of a solution of a weak acid HY (0.10 M). If $$\lambda _{{x^ - }}^0 \approx \lambda _{{y^ - }}^0$$ the difference in their pK_a values, pK_a(HX) - pK_a(HY), is (consider degree of ionization of both acids to be << 1)

When O₂ is adsorbed on a metallic surface, electron transfer occurs from the metal to O₂. The true statement(s) regarding this adsorption is(are)

Paragraph
When 100 mL of 1.0 M KCl was mixed with 100 mL of 1.0 M NaOH in an insulated beaker at constant pressure, a temperature increase of 5.7^o 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 constant (-57.0 kJ/mol), this experiment could be used to measure the calorimeter constant. In a second experiment (Expt. 2) 100 mL of 2.0 M acetic acid (K_a = 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^o C was measured. (Consider heat capacity of all solutions as 4.2 J/gK and density of all solutions as 1.0 g m/L)
Question
The pH of the solution after Expt. 2 is