Calculate e.m.f. of the cell containing nickel and copper electrodes. Given that :
`E_(Ni^(2+)//Ni)^(@)=-0.25 V , E_(Cu^(2+)//Cu)^(@)=+0.34 V.`

Explanation

To calculate the e.m.f. (electromotive force) of the cell containing nickel and copper electrodes, we will follow these steps:

### Step 1: Identify the Standard Reduction Potentials
We are given the standard reduction potentials:
- For nickel: \( E^\circ_{Ni^{2+}/Ni} = -0.25 \, V \)
- For copper: \( E^\circ_{Cu^{2+}/Cu} = +0.34 \, V \)

### Step 2: Determine the Anode and Cathode
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