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The standard potentials at 25^@C for the...

The standard potentials at `25^@C` for the following half reactions are given against them
` Zn^(2+) +2e^(-) rarr Zn, E^0 =-0 . 762 V `
`Mg^(2+) +2e^(-) rarr Mg, =- 2.37 V`.
When zinc dust is added to a solution of magnesium chloride .`

A

no reaction will take place

B

zinc chloride is formed

C

zinc dissolves in the solution

D

magnesium is precipitated .

Text Solution

Verified by Experts

The correct Answer is:
A
`Zn + Mg^(2+) to Zn^(2+) + Mg` .
`E_("cell")^(@) = E_(Zn| Zn^(2+))^(@) + E_(Mg^(2+) | Mg)^(@)`
`= + 0.762 - 2.37 = - 1.608` V
As EMF comes out to be negative , no reaction will take place .
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