For the following three reactions a, b and c, equilibrium constants are given:
a. CO (g) + H₂O (g) $$\leftrightharpoons$$ CO₂(g) + H₂ (g) ; K₁
b. CH₄ (g) + H₂O (g) $$\leftrightharpoons$$ CO(g) + 3H₂ (g) ; K₂
c. CH₄ (g) + 2H₂O (g) $$\leftrightharpoons$$ CO₂(g) + 4H₂ (g) ; K₃

The pK_a of a weak acid, HA, is 4.80. The pK_b of a weak base, BOH, is 4.78. The pH of an aqueous solution of the corresponding salt, BA, 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 :

In the following sequence of reactions, the alkene affords the compound ‘B’
CH₃ - CH = CH - CH₃ $$\buildrel {{O_3}} \over \longrightarrow $$ A $$\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Zn}^{H{}_2O}} $$ B
The compound B is