Question

The standard cell potential (E°cell) of the reaction below is -0.55 V. The value of Δ G° for the reaction is ________ J/mol. I2 (s) + 2Br- (aq) → 2I- (aq) + Br2 (l)

Answer 1

`\Delta G^(0)` for the given reaction is 106150 J/mol

Step-by-step explanation:

Oxidation:
`2Br^(-)-2e^(-)\rightarrow Br_(2)`

Reduction:
`I_(2)+2e^(-)\rightarrow 2I^(-)`

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Overall:
`I_(2)+2Br^(-)\rightarrow 2I^(-)+Br_(2)`

We know,
`\Delta G^(0)=-nFE^(0)`

where, n is number of electron exchanged during overall reaction and 1 F equals to 96500 C/mol

Here, n = 2 and
`E^(0)=-0.55V`

So,
`\Delta G^(0)=-(2)* (96500C/mol)* (-0.55V)=106150J/mol`