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Cell concentrations are concentration dependent.

The Nernst equation useful to calculate cell potential at non-standard conditions.

E_{cell} = EÂ°_{cell} - RT/nF lnQ

E_{cell} = Cell potential at non-standard conditions

EÂ° = Cell potential at standard conditions

R = Universal gas constant, 8.314 JK^{-1}mol^{-1}

T = Temperature in Kelvin

n = Number of electrons transferred in the equation

F = Faraday's constant, 96,487 C mol^{-1}

Q = Reaction quotient

For a reaction under normal conditions,

aA + bB â†’ cC + dD

Q = ([C]^{c}[D]^{d})/([A]^{a}[B]^{b})

E_{cell} = EÂ°_{cell} - RT/nF lnQ

E_{cell} = EÂ°_{cell} - 0.0592/n lnQ

The cell voltage of a Daniel cell running with 0.1 molar zinc sulphate and 0.5 molar copper (II) sulphate at 25 ^{0}C.

n = 2, [Zn] = [Cu] = 1

E_{cell} = EÂ°_{cell} - 0.0592/n ln([Zn^{2+}]/[Cu^{2+}])

E_{cell} = EÂ°_{cell} - 0.0592/n ln([0.1]/[0.5])

E_{cell} = EÂ°_{cell} - 0.0592/n ln 0.2

E_{cell} = 1.12 V

**Appilcations of Nernst Equation:**

The Nernst equation can be used to calculate E_{cell} at different concentrations.

Compared to standard conditions, E_{cell} will increase as the reactant ion concentration increases (Q decreases).

Compared to standard conditions, E_{cell} will decrease if the product ion concentration increases (as Q increases).

Concentration cells can be established.

pH meters are also work on the principle of Nernst equation.

The Gibbs free energy can be calculated from E_{cell}.

The equilibrium constant can be calculated from E_{cell}.

Cell concentrations are concentration dependent.

The Nernst equation useful to calculate cell potential at non-standard conditions.

E_{cell} = EÂ°_{cell} - RT/nF lnQ

E_{cell} = Cell potential at non-standard conditions

EÂ° = Cell potential at standard conditions

R = Universal gas constant, 8.314 JK^{-1}mol^{-1}

T = Temperature in Kelvin

n = Number of electrons transferred in the equation

F = Faraday's constant, 96,487 C mol^{-1}

Q = Reaction quotient

For a reaction under normal conditions,

aA + bB â†’ cC + dD

Q = ([C]^{c}[D]^{d})/([A]^{a}[B]^{b})

E_{cell} = EÂ°_{cell} - RT/nF lnQ

E_{cell} = EÂ°_{cell} - 0.0592/n lnQ

The cell voltage of a Daniel cell running with 0.1 molar zinc sulphate and 0.5 molar copper (II) sulphate at 25 ^{0}C.

n = 2, [Zn] = [Cu] = 1

E_{cell} = EÂ°_{cell} - 0.0592/n ln([Zn^{2+}]/[Cu^{2+}])

E_{cell} = EÂ°_{cell} - 0.0592/n ln([0.1]/[0.5])

E_{cell} = EÂ°_{cell} - 0.0592/n ln 0.2

E_{cell} = 1.12 V

**Appilcations of Nernst Equation:**

The Nernst equation can be used to calculate E_{cell} at different concentrations.

Compared to standard conditions, E_{cell} will increase as the reactant ion concentration increases (Q decreases).

Compared to standard conditions, E_{cell} will decrease if the product ion concentration increases (as Q increases).

Concentration cells can be established.

pH meters are also work on the principle of Nernst equation.

The Gibbs free energy can be calculated from E_{cell}.

The equilibrium constant can be calculated from E_{cell}.