A voltaic cell that uses the reaction

Tl3+(aq) + 2 Cr2+(s) �¨ Tl+(aq) + 2 Cr3+(aq)
has a measured standard cell potential of +1.19 V.

determine E�‹red for the reduction of Tl3+(aq) to Tl+(aq).

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To determine the reduction potential (E�‹red) for the reduction of Tl3+(aq) to Tl+(aq) in the given voltaic cell, we need to use the Nernst equation.

The Nernst equation relates the cell potential (E�‹cell) to the standard cell potential (E�‹cell°), the reaction quotient (Q), the gas constant (R), the temperature (T), and the number of electrons transferred (n) in the balanced equation.

The Nernst equation can be written as:

E�‹cell = E�‹cell° - (0.0592 V/n) * log(Q)

Where:
- E�‹cell is the cell potential
- E�‹cell° is the standard cell potential
- Q is the reaction quotient
- 0.0592 V/n is the Nernst constant (at 298 K)

In this case, we are given the standard cell potential (E�‹cell°) of +1.19 V. The balanced equation shows that the number of electrons transferred (n) is 3 (because three electrons are involved in the reduction of Tl3+(aq) to Tl+(aq)).

Now, we need to calculate the reaction quotient (Q). The reaction quotient is calculated using the concentrations of the species involved in the reaction.

For the given reaction:
Tl3+(aq) + 2 Cr2+(s) �¨ Tl+(aq) + 2 Cr3+(aq)

The reaction quotient (Q) is given by:
Q = [Tl+][Cr3+]^2 / [Tl3+][Cr2+]^2

Since the species Tl3+ and Cr2+ are not mentioned to have a concentration, it can be assumed that their concentrations are 1 M (standard state).
Thus, the reaction quotient simplifies to:
Q = [Tl+][Cr3+]^2

Now, let's substitute the given values into the Nernst equation:

E�‹cell = E�‹cell° - (0.0592 V/3) * log(Q)

E�‹cell = 1.19 V - (0.0197 V) * log([Tl+][Cr3+]^2)

To solve for E�‹red, we need to rearrange the equation and isolate E�‹red:

E�‹red = E�‹cell - E�‹cell° + (0.0592 V/3) * log(Q)

By substituting the given values, you can calculate the reduction potential (E�‹red) for the reduction of Tl3+(aq) to Tl+(aq).

You need concentrations or Eox for Cr.

then do you subtract the given cell potential from that?