In the extraction of chlorine from brine ............

a. G for the overall reaction is negative.

b. G for the overall reaction is positive.

c. E for the overall reaction has a negative value.

d. E for the overall reaction has a positive value.

Choose the correct option

1. (a, b)
2. (b, c)
3. (c, d)
4. (a, d)


 
 


Hint: For electrolytic cell, Ecello value is negative.

Electrolysis of brine solution is used to extract chlorine. Overall chemical reaction occurring in this process and the value of G can be shown as

2
H2Ol + 2Cl-aq H2g+ Cl2g + 2OH-aq

For the given reaction, value of G° is 422 kJ
Using G°=-nFE°, the value of E°=E°-2.2V.
Therefore, G° for the overall reaction is positive and E° has negative value.

The reaction is non-spontaneous and with the help of external process, in this case electricity is an external source which is used.

With the help of electricity non-spontaneous reaction is converted into spontaneous reaction in the electrolytic cell.