The standard reduction potential of `Fe^(3+), Fe^(2+)//Pt` is `+ 0.771V`. This half cell is connected with another half cell such that e.m.f. of the cell is 0.771V. What is the other half cell ?

Explanation

(i) The emf of the standard hydrogen electrode is Zero volts.
`Fe//Fe^(3+)Fe^(2+), H^(2)""_((atm)pt)" "E=0.771V`
E measured `=E_(R)-E_(L)`
(ii) emf of SHE = 0
`E_("measured")=0.771V-0=0.771V`
(iii) `therefore` The other half cell connected is Standard Hydrogen Electrode (SHE).