The potential of the cell at `25^(@)C ` is Given `pK_(a)` of `CH_(3)COOH` and `pK_(b)` of `NH_(4)OH=4.74`A. `-0.04V`B. `0.04V`C. `-0.189V`D. `0.189V`

The potential of the cell at `25^(@)C ` is Given `pK_(a)` of `CH_(3)C

1.	The potential of the cell at `25^(@)C ` is Given `pK_(a)` of `CH_(3)COOH` and `pK_(b)` of `NH_(4)OH=4.74`A. `-0.04V`B. `0.04V`C. `-0.189V`D. `0.189V`
Answer» Correct Answer - c It is concentration cell, therefore, `E^(c-)._(cell)=0.` Acidic buffer at anode `:` `:. pH=pK_(a)+log[(Sal t)/(Aci d)]` `=4.74+log .(0.1)/(0.01)=4.74+1=5.74` Basic buffer at cathode `:` `:. pOH=pK_(b)+log[(Sal t)/(Base)]` `=4.74+log.(0.2)/(0.1)` `=4.74+0.03=5.04` `:. pH=14-5.04=8.96` `E_(cell)=-0.059(pH_(c)-pH_(a))` `=-0.050(8.96-5.74)` `=-0.059xx3.22=-0.189V`

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The potential of the cell at `25^(@)C ` is Given `pK_(a)` of `CH_(3)COOH` and `pK_(b)` of `NH_(4)OH=4.74`A. `-0.04V`B. `0.04V`C. `-0.189V`D. `0.189V`

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