What would be the magnitude of `EMF` of the following cell`:` at `25^(@)C` ? The ionization constant of acetic acid, `K_(a)~ 10^(-5)`, while that of formic acid, `K_(a)~10^(-4)`A. `0.0295V`B. `0.059V`C. `-0.059V`D. `-0.0295V`

What would be the magnitude of `EMF` of the following cell`:` at `25^

1.	What would be the magnitude of `EMF` of the following cell`:` at `25^(@)C` ? The ionization constant of acetic acid, `K_(a)~ 10^(-5)`, while that of formic acid, `K_(a)~10^(-4)`A. `0.0295V`B. `0.059V`C. `-0.059V`D. `-0.0295V`
Answer» Correct Answer - b At anode `:` `0.1M` acetic acid `+0.1M` sodium acetate `implies` Acidic buffer. `:. pH_(a)=pK_(a)+log [(sal t)/(Aci d)]" "(pK_(a(CH_(3)COOH))=5)` `=5+log((0.1)/(0.1))=5` At cathode `:` `0.1M` formic acid `+0.1M` sodium formate `implies` Acidic buffer. `:.pH_(c)=pK_(a)+log((0.1)/(0.1))" "[pK_(a(HCOOH))=4]` `pH_(c)=4` `E_(cell)=-0.059(pH_(c)-pH_(a))=-0.059*4-5)=0.059V`

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What would be the magnitude of `EMF` of the following cell`:` at `25^(@)C` ? The ionization constant of acetic acid, `K_(a)~ 10^(-5)`, while that of formic acid, `K_(a)~10^(-4)`A. `0.0295V`B. `0.059V`C. `-0.059V`D. `-0.0295V`

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