Question

Which from following is CORRECT expression for E_cell of following cell?

\[\ce{Pb_{(s)} | Pb^++_{(1 m)} || Ag^+_{(0.1 m)} | Ag_{(g)}}\] at 25°C?

Options

• E_cell =  (\[\ce{E^\circ_{cell}}\] + 0.0296) V

• E_cell =  (\[\ce{E^\circ_{cell}}\] − 0.0296) V

• E_cell =  (\[\ce{E^\circ_{cell}}\] − 0.0592) V

• E_cell =  (\[\ce{E^\circ_{cell}}\] + 0.0592) V

Answer 1

E_cell =  (\[\ce{E^\circ_{cell}}\] − 0.0592) V

Explanation:

Cell representation:

\[\ce{Pb_{(s)} | Pb^++_{(1 m)} || Ag^+_{(0.1 m)} | Ag_{(s)}}\]

Reaction:

\[\ce{Pb_{(s)} + 2Ag^+_{(0.1 m)} -> Pb^++_{(1 m)} + 2Ag_{(s)}}\]

Nernst equation at 25°C:

E_cell = \[\ce{E^\circ_{cell}}\] `- 0.0592/2 log_10  [Pb^(++)]/[Ag^+]^2`

E_cell = \[\ce{E^\circ_{cell}}\] `- 0.0592/2 log_10  1/0.1^2`

E_cell = \[\ce{E^\circ_{cell}}\] `- 0.0592/2 log_10 100`

E_cell = \[\ce{E^\circ_{cell}}\] `- 0.0592/2 xx2`

E_cell = (\[\ce{E^\circ_{cell}}\] `- 0.0592)` V