The equilibrium constants K_P1 and K_P2 for the reactions X $$\leftrightharpoons$$ 2Y and Z $$\leftrightharpoons$$ P + Q, respectively are in the ratio of 1 : 9. If the degree of dissociation of X and Z be equal then the ratio of total pressure at these equilibria is :

Standard entropy of X₂, Y₂ and XY₃ are 60, 40 and 50 JK⁻¹ mol⁻¹ , respectively. For the reaction,
$${1 \over 2} X_2$$ + $${3 \over 2} Y_2 \to$$ XY₃, $$\Delta H$$ = -30 kJ, to be at equilibrium, the temperature will be :

Oxidising power of chlorine in aqueous solution can be determined by the parameters indicated below:
$${1 \over 2}C{l_2}(g)$$ $$\buildrel {{1 \over 2}{\Delta _{diss}}{H^\Theta }} \over \longrightarrow $$ $$Cl(g)$$ $$\buildrel {{\Delta _{eg}}{H^\Theta }} \over \longrightarrow $$ $$C{l^ - }(g)$$ $$\buildrel {{\Delta _{Hyd}}{H^\Theta }} \over \longrightarrow $$ $$C{l^ - }(aq)$$
(Using the data, $${\Delta _{diss}}H_{C{l_2}}^\Theta $$ = 240 kJ/mol, $${\Delta _{eg}}H_{Cl}^\Theta $$ = -349 kJ/mol, $${\Delta _{hyd}}H_{C{l^ - }}^\Theta $$ = - 381 kJ/mol) will be :

Amount of oxalic acid present in a solution can be determined by its titration with $$KMn{O_4}$$ solution in the presence of $${H_2}S{O_4}.$$ The titration gives unsatisfactory result when carried out in the presence of $$HCl,$$ because $$HCl$$ :