In which of the following cells E text cell =E° cell ?

Question

In which of the following cells E text cell =E° cell ? (A) Cu (s)| Cu 2+(0.01 M )|| Ag +(0.1 M )| Ag(s) (B) Pt ( H 2)| pH =1|| Zn 2+(0.01 M )| Zn (s) (C) Pt( H 2)| pH =1|| Zn 2+(1 M )| Zn (s) (D) Pt( H 2)| H +=0.01 M || Zn 2+(0.01 M )| Zn (s)

Tardigrade Admin · Accepted Answer

From Nernst equation, E text cell =E text cell °-(0.0591/n F) log Q. If Q=1, log Q=0 so, E text cell =E text cell ° This condition is found in (a) and (b).

Q. In which of the following cells $E_{cell} = E^{\circ}$ cell ?

$C u (s) ∣ ∣ C u^{2 +} (0.01 M) ∣ ∣ ∣ A g^{+} (0.1 M) ∣ A g (s)$

$Pt (H_{2}) ∣ p H = 1∣ ∣ ∣ Z n^{2 +} (0.01 M) ∣ ∣ Z n (s)$

$Pt (H_{2}) ∣ p H = 1∣ ∣ ∣ Z n^{2 +} (1 M) ∣ ∣ Z n (s)$

$Pt (H_{2}) ∣ H^{+} = 0.01 M ∣ ∣ ∣ Z n^{2 +} (0.01 M) ∣ ∣ Z n (s)$

From Nernst equation,
$E_{cell} = E_{cell}^{\circ} - \frac{0.0591}{n F} lo g Q$ .
If $Q = 1, lo g Q = 0$ so, $E_{cell} = E_{cell}^{\circ}$
This condition is found in (a) and (b).

Q. In which of the following cells Ecell ​=E∘ cell ?

Cu(s)∣∣​Cu2+(0.01M)∣∣​∣Ag+(0.1M)∣Ag(s)

Pt(H2​)∣pH=1∣∣∣​Zn2+(0.01M)∣∣​Zn(s)

Pt(H2​)∣pH=1∣∣∣​Zn2+(1M)∣∣​Zn(s)

Pt(H2​)∣H+=0.01M∣∣∣​Zn2+(0.01M)∣∣​Zn(s)