The standard reduction potentials for Zn2+/Zn, Ni2+/Ni and Fe2+/Fe are -0.76, - 0.23 and -0.44 V respectively. The reaction X + Y2+ → X2+ + Y will be spontaneous when :

Question

The standard reduction potentials for Zn2+/Zn, Ni2+/Ni and Fe2+/Fe are -0.76, - 0.23 and -0.44 V respectively. The reaction X + Y2+ → X2+ + Y will be spontaneous when : (A) X = Ni, Y = Fe (B) X = Ni, Y = Zn (C) X= Fe, Y = Zn (D) X= Zn, Y = Ni

Tardigrade Admin · Accepted Answer

X + Y2+ → X2+ + Y For reaction to be spontaneous Eº° must be positive. E°Zn / Zn+2 + E°Ni2+ / Ni = 0.76 + (- 0.23) = + 0.53 (positive)

Q. The standard reduction potentials for $Z n^{2 +} / Z n, N i^{2 +} / N i$ and $F e^{2 +} / F e$ are -0.76, - 0.23 and -0.44 V respectively. The reaction $X + Y^{2 +} \to X^{2 +} + Y$ will be spontaneous when :

$X = N i, Y = F e$

$X = N i, Y = Z n$

$X = F e, Y = Z n$

$X = Z n, Y = N i$

$X + Y^{2 +} \to X^{2 +} + Y$
For reaction to be spontaneous $E º^{\circ}$ must be positive.
$E_{Z n / Z n^{+ 2}}^{\circ} + E_{N i^{2 +} / N i}^{\circ} = 0.76 + (- 0.23) = + 0.53$ (positive)

Q. The standard reduction potentials for Zn2+/Zn,Ni2+/Ni and Fe2+/Fe are -0.76, - 0.23 and -0.44 V respectively. The reaction X+Y2+→X2++Y will be spontaneous when :

X=Ni,Y=Fe

X=Ni,Y=Zn

X=Fe,Y=Zn

X=Zn,Y=Ni