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Preferential discharge of ions during electrolysis

Answer Text:
Preferential discharge of ions during electrolysis
- The products of electrolysis of any given electrolyte depend on the ions present in an electrolyte.
- Commonly most molten electrolytes have only two ions; a cation and an anion and are termed Binary electrolytes.
- As the electrolyte decomposes, ions collect/move to the opposite poles.
- Negatively charged ions move to the Anode; the positive electrode, while the positively charged ions move to the cathode, the negative electrode;
- Regardless of how many ions move to an electrode; only one can be discharged to give a product.
- Both cations and anions have a preferential discharge series.
a) Discharge for cations
-Cations are discharged by reduction (accepting electrons) to form their respective products.
The ease of reduction of cations depends on their position of electrochemical
series. Thus #Ag^(+)# is most readily discharged as it’s the weakest reducing agent.
b) Discharge for anions
-Anions are discharged by oxidation (electron loss) to form their respective products.
Discharge of anions is viz.