Why do different substances produce different products in electrolysis?

Different substances produce different products in electrolysis because they have unique chemical compositions and reactivity.

Electrolysis is a process that uses an electric current to drive a non-spontaneous chemical reaction. This process involves the movement of electrons from the anode (positive electrode) to the cathode (negative electrode), leading to chemical changes. The specific substances involved in the electrolysis determine the nature of these chemical changes and thus the products formed.

Different substances have unique chemical compositions, meaning they are made up of different types and numbers of atoms. These atoms are held together by chemical bonds, which can be broken and reformed during electrolysis. The way these bonds break and reform is specific to the substance involved. For example, if you electrolyse a solution of copper sulfate, you will get copper at the cathode and oxygen at the anode. However, if you electrolyse a solution of sodium chloride, you will get hydrogen at the cathode and chlorine at the anode. This is because copper sulfate and sodium chloride are made up of different atoms that react differently during electrolysis.

Furthermore, different substances have different reactivity. Reactivity refers to how readily a substance undergoes a chemical reaction. In the context of electrolysis, more reactive substances are more likely to be involved in the chemical changes occurring at the electrodes. For instance, in a solution containing both copper ions and hydrogen ions, copper ions are less reactive and will be discharged at the cathode instead of hydrogen ions. This difference in reactivity further contributes to the formation of different products during electrolysis.

In conclusion, the unique chemical compositions and reactivity of different substances determine the products they form during electrolysis. This is why electrolysis of different substances yields different results.