Home
Class 12
CHEMISTRY
The EMF of Westron standard cell is 1.01...

The `EMF` of Westron standard cell is `1.0153` at `20^(@)C` and `1.01807` at `25^(@)C`. Calculate`DeltaG,DeltaH,` and `Delta S` for the cell reaction at `25^(@)C`.

Text Solution

Verified by Experts

Westron cell reaction is
`Cd_(s) + Hg_(2)SO_(4)(s) to CdSO_(4)(aq) + 2Hg_(l)`
`n_("cell")=2`
`(dE)/(dT)_(P) =(1.01807 - 1.01530)/(298-293) = 5.54 xx 10^(-4)V deg^(-1)`
`Delta S = nF((dE)/(dT))_(P)`
`=2 xx 96500 xx 5.54 xx 10^(-4) V deg^(-1)`
`DeltaG = -nFE = -2 xx 96500 xx 1.01807` (at `25^(@)` C)
`=-196.45 kJ mol^(-1)`
`DeltaH = -DeltaG + T DeltaS`
`=-196.45 kJ + 298 xx 106.9 xx 10^(-3) kJ mol^(-1)`
`=-196.45 + 31.85 = -164.6 kJ mol^(-1)`
`DeltaH = nF [T ((dE)/(dT))_(P)-E]`

`=2 xx 96500 [298 xx 5.54 xx 10^(-4) - 1.01807]`
`=-164.58 kJ mol^(-1) = -164.6 kJ mol^(-1)`
Promotional Banner

Similar Questions

Explore conceptually related problems

The potential of the following cell at 25^(@)C is

For the cell Zn|ZnCl_(2)(m)|AgCl,E is 1.24V at 25^(@)C and 1.260V at 35^(@)C of m=10^(-3) . Write down the cell reaction and calculate DeltaG, DeltaH, and DeltaS at 25^(@)C .

The standard emf of the cell. Cd(s) | CdCl_(2) (aq) rightarrow 2Ag(s) + Cd^(2+) (aq) + 2Cl^(-)(aq) is 0.6915 V at 0^(@) and 0.6753 V at 25^(@)C . The DeltaH^(@) of the reaction at 25^(@)C is:

The standard emf of the cell, Cd(s) |CdCI_(2) (aq) (0.1M)||AgCI(s)|Ag(s) in which the cell reaction is Cd(s) +2AgCI(s) rarr 2Ag(s) +Cd^(2+) (aq) is 0.6915 V at 0^(@)C and 0.6753V at 25^(@)C . The DeltaH of the reaction at 25^(@)C is,-

The EMF of the following cell : Cd(s)|CdCl_(2)(0.10M)|AgCl(s)|Ag(s) is 0.6915V at 0^(@)C and 0.6753V at 25^(@)C . The DeltaH of reaction in kJ at 25^(@)C is

The standard potential of the following cell is 0.23 V at 15^(@)C and 0.21V at 35^(@)C . Pt|H_(2) |HCl(aq) |Agcl (s)|g(s) (i) write the cell reaction . (ii) Calculate DeltaH^(@) and DeltaS^(@) for the cell reaction by assuming that these quantities remain unchanged in the range 15^(@)C to 35^(@)C . (iii) calculate the solubility of AgCl in water at 25^(@)C . Give , the standard reduction potential of the (Ag^(+)(aq) //Ag(s) is 0.80 V at 25^(@) C .