STD 11 - 3. Classification of elements and periodicity in properties — NEET STD 11 Science — Question

$B.E. (H-H) = x_1 ; B.E. (O = O) = x_2$ ;

$B.E. (O -H) = x_3$

Heat of vaporisation of water $= x_4$ then $\Delta {H_f}$ [heat of formation of liquid water] is

${I^ - }(aq.) + MnO_4^ - (aq.)\xrightarrow[{weakly\,\,O{H^ - }}]{{Neutral\,\,or}}Y + Mn{O_2}$

$MnO_4^ - (aq.) + M{n^{2 + }}(aq.)\xrightarrow{{ZnS{O_4}}}Z + 4{H^ + }$

Products $X,\,Y$ and $Z$ are respectively :

$Zn_{(s)} + Ag_2O_{(s)} + H_2O_{(l)} \rightleftharpoons  $$2Ag_{(s)} + Zn^{2+}_{(aq)}+ 2OH^-_{(aq)}$

If half cell potentials are

$Zn^{2+}_{(aq)} + 2e^- \rightarrow Zn_{(s)}\,;\,\, E^o = - 0.76\, V$

$Ag_2O_{(s)} + H_2O_{(l)} + 2e^- \rightarrow 2Ag_{(s)} + 2OH^-_{(aq)}\,,$$E^o = 0.34\, V$

The cell potential will be ........... $V.$