Tollen reagent is used for the detection of aldehydes. When a solution of `AgNO_(3)` is added to glucose with `NH_(4)OH`, then gluconic acid is formed. `Ag^(o+)+e^(-) rarr Ag," "E^(c-)._(red)=0.8V` `C_(6)H_(12)O_(6)rarr underset(Gluconic aci d)(C_(6)H_(12)O_(7)+)2H^(o+)+2e^(-) , " "E^(c-)._(o x i d ) =-0.05V` `[Ag(NH_(3))_(2)]^(o+)+e^(-) rarr Ag(s)+2NH_(3), " "E^(c-)._(red)=0.337V` `[Use2.303xx(RT)/(F)=0.0592` and `(F)/(RT)=38.92at 298 K ]` `2Ag^(o+)+C_(6)H^(12)O_(6)+H_(2)O rarr 2Ag^(s)+C_(6)H_(12)O_(7)+2H^(o+)` Find `lnK` of this reaction.A. `66.13`B. `58.38`C. `28.30`D. `46.29`

Tollen reagent is used for the detection of aldehydes. When a solution

1.	Tollen reagent is used for the detection of aldehydes. When a solution of `AgNO_(3)` is added to glucose with `NH_(4)OH`, then gluconic acid is formed. `Ag^(o+)+e^(-) rarr Ag," "E^(c-)._(red)=0.8V` `C_(6)H_(12)O_(6)rarr underset(Gluconic aci d)(C_(6)H_(12)O_(7)+)2H^(o+)+2e^(-) , " "E^(c-)._(o x i d ) =-0.05V` `[Ag(NH_(3))_(2)]^(o+)+e^(-) rarr Ag(s)+2NH_(3), " "E^(c-)._(red)=0.337V` `[Use2.303xx(RT)/(F)=0.0592` and `(F)/(RT)=38.92at 298 K ]` `2Ag^(o+)+C_(6)H^(12)O_(6)+H_(2)O rarr 2Ag^(s)+C_(6)H_(12)O_(7)+2H^(o+)` Find `lnK` of this reaction.A. `66.13`B. `58.38`C. `28.30`D. `46.29`
Answer» Correct Answer - b Cell reaction `:` `i. Ag^(o+)+e^(-) rarr Ag(s)," "E^(c-)._(red)=0.8V` `ii. C_(6)H_(12)O_(6)rarr C_(6)H_(12)O_(7)+2H^(o+)+2e^(-), " "E_(o x i d)=-0.05V` Hence, for reaction `2Ag^(o+)+C_(6)H_(12)O_(6)+H_(2)Orarr 2Ag(s)+C_(6)H_(12)O_(7)+2H^(o+)` `E^(c-)._(cell)=0.8-0.05` `=0.75V` `E_(cell)=E^(c-)._(cell)-(2.303)/(nF)log K` At equilibrium, `E_(cell)=0` `:. E^(c-)._(cell)=(2.303RT)/(nF)log K` `0.75=(0.0592)/(2) log K` `log K =(2xx0.75)/(0.0592)=25.33` or `ln K =2.303xxlogk` `=2.303xx25.33` `=58.35`

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