A galvanic cell based on these half reactions is set up under standard conditions where each solution is 1.00 l and each electrode weighs exactly 100.0 g. how much will the cd electrode weigh when the nonstandard potential of the cell is 0.02543 v

Respuesta :

Answer:

When the nonstandard potential of the cell is 0.02543 v the weight of the cathode is 120.575 g weight.

Explanation:

The half reactions are as follows;

Ni²⁺ + 2 e⁻ → Ni E₀ = -0.231 V

Pb²⁺ + 2 e⁻ → Pb E₀ = -0.133 V​

n = 2

Here we have the Nernst equation given by

[tex]E_{cell} = E_{cell}^0 - \frac{RT}{nF} lnQ = E_{cell}^0 - (\frac{0.0591 V}{n} )log Q[/tex]

Where:

[tex]E_{cell}^0[/tex] = 0.098 V

We have, when [tex]E_{cell}[/tex] = 0.02543 V

[tex]E_{cell}[/tex] - [tex]E_{cell}^0[/tex]  = 0.02543 - 0.098 = -0.07257 V = [tex]- (\frac{0.0591 V}{2} )log Q[/tex]

log Q = 2.456

Q = [tex]10^{2.456}[/tex]  = 285.65

Therefore the number of electron will be

285.65 = the ratio of the Ni²⁺/Pb

Therefore if the initial concentration is 1×10⁻¹ M, we have

[tex]\frac{0.1 + x}{0.1 - x} = 285.65[/tex]  

x = 9.93 × 10⁻² Moles

Therefore since 1 mole of Pb = 207.2 g

9.93 × 10⁻² × 207.2 g = 20.575 g

Mass of Pb = 120.575 g.