Consider the following cell reaction: 2 Fe ( s )+ O 2( g )+4 H +( aq ) arrow 2 Fe 2+( aq )+2 H 2 O ( l ) ; E°=1.67 V At [ Fe 2+]=10-3 M , p( O 2)=0.1 atm and pH =3, the cell potential at 25° C is

Question

Consider the following cell reaction: 2 Fe ( s )+ O 2( g )+4 H +( aq ) arrow 2 Fe 2+( aq )+2 H 2 O ( l ) ; E°=1.67 V At [ Fe 2+]=10-3 M , p( O 2)=0.1 atm and pH =3, the cell potential at 25° C is (A) 1.47 V (B) 1.77 V (C) 1.87 V (D) 1.57 V

Tardigrade Admin · Accepted Answer

The half reactions are Fe(s) longrightarrow Fe2+(aq) + 2e- × 2 O2(g) + 4H+ + 4e- longrightarrow 2H2 O 2Fe(s)+O2(g) + 4H+ longrightarrow + 2Fe2+(aq)+ 2H2 O (l); E=E°-(0.059/4) log((10-3)2/(10-3)4 (0.1))=1.57 V

Q. Consider the following cell reaction:
$2 F e (s) + O_{2} (g) + 4 H^{+} (a q) \to 2 F e^{2 +} (a q) + 2 H_{2} O (l); E^{\circ} = 1.67 V$
At $[F e^{2 +}] = 1 0^{- 3} M, p (O_{2}) = 0.1 a t m$ and $p H = 3$ , the cell potential at $2 5^{\circ} C$ is

$1.47 V$

$1.77 V$

$1.87 V$

$1.57 V$

The half reactions are
$F e (s) ⟶ F e^{2 +} (a q) + 2 e^{-} \times 2$
$O_{2} (g) + 4 H^{+} + 4 e^{-} ⟶ 2 H_{2} O$
$2 F e (s) + O_{2} (g) + 4 H^{+} ⟶ + 2 F e^{2 +} (a q) + 2 H_{2} O (l);$
$E = E^{\circ} - \frac{0.059}{4} lo g \frac{( 1 0 ^{- 3} ) ^{2}}{( 1 0 ^{- 3} ) ^{4} ( 0.1 )} = 1.57 V$

Q. Consider the following cell reaction: 2Fe(s)+O2​(g)+4H+(aq)→2Fe2+(aq)+2H2​O(l);E∘=1.67V At [Fe2+]=10−3M,p(O2​)=0.1atm and pH=3, the cell potential at 25∘C is

1.47V

1.77V

1.87V

1.57V