What is the approximate standard free energy change per mole of Zn (in Kj `mol^(-1)` ) for a Daniel cell at 298 K?

Options

A. `-212.3`
B. `230.0`
C. `0.0`
D. `-1.10`

Answer

A

Explanation

For Danicell cell we have
`Zn (s) + Cu ^(2+) (aq) to Zn ^(2+)(aq) + Cu (s)`
Gibbs free energy =- nFE
n = number of electrons =2
F = Faraday's constant `= 96500C`
E = emf of cell `=1.1V`
`therefore` Gibbs free energy `=-2xx 96500 xx1.1J =- 212.3kJ`