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 plaeB. Zinc chloride is formedC. Zinc dissolve in solutionD. Magnesium is preciptiated

The standard potentials at `25^@C` for the following half reactions ar

1.	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 plaeB. Zinc chloride is formedC. Zinc dissolve in solutionD. Magnesium is preciptiated
Answer» Correct Answer - A ` Zn+ MgCl_2rarr ZnCl_2+Mg` `:.E_("cell")^@ = E_(Zn//Zn^(+2))^@ + E_(Mg^(+2)//Mg)^@ = + 0.762 - 2.37` `-= 1.608 V`. Here, ` E_("cell")^@` is negative so no reaction will take place.

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