A) \[-114.25\text{ }kJ\,mo{{l}^{-1}}\]
B) \[114.25\text{ }kJ\text{ }mo{{l}^{-1}}\]
C) \[228.5\text{ }kJ\,mo{{l}^{-1}}\]
D) \[-228.5\text{ }kJ\text{ }mo{{l}^{-1}}\]
Correct Answer: D
Solution :
[d] \[{{H}_{2}}(g)+\frac{1}{2}{{O}_{2}}(g)\xrightarrow{{}}{{H}_{2}}O(l);\] \[\Delta H=-285.8\text{ }kJ\] .... (i) \[{{H}^{+}}(aq)+O{{H}^{-}}(aq)\xrightarrow{{}}{{H}_{2}}O(l);\] \[\Delta H=-57.3kJ\] .... (ii) \[\frac{1}{2}{{H}_{2}}(g)+aq\xrightarrow{{}}{{H}^{+}}{{(aq)}^{+}}{{e}^{-}};\Delta H=0\] (by convention) .... (iii) (ii) - (iii) gives, \[\frac{1}{2}{{H}_{2}}\left( g \right)+\frac{1}{2}{{O}_{2}}\left( g \right)+{{e}^{-}}+aq\xrightarrow{{}}O{{H}^{-}}\left( aq \right)\] \[\Delta H=-285.8+57.3=-228.5kJ\]
You need to login to perform this action.
You will be redirected in
3 sec
