In the electrolysis of dilute sulphuric acid using platinum electrodes, the products obtained at the anode and cathode are:
Anode Cathode
Sulphur hydrogen
Hydrogen oxygen
Oxygen Hydrogen
Hydrogen sulphate ions
Sulphur oxygen
Explanation
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the answer ought to be C
here is why
When you electrolyze dilute sulfuric acid (H2SO4) with platinum electrodes, here's why you get oxygen gas at the anode and hydrogen gas at the cathode:
1. Dissociation and Competition: Sulfuric acid dissociates in water to form hydrogen (H+) and sulfate (SO4²-) ions. Water itself also undergoes autoionization, forming H+ and hydroxide (OH-) ions. During electrolysis, both H+ and OH- ions are attracted to the electrodes.
2. Favorable Reactions: At the cathode (negative electrode), reduction occurs. Ideally, H+ ions would be reduced to hydrogen gas (H2). While it might seem like sulfate ions could also be reduced, it's generally less favorable for them to gain electrons compared to H+. Additionally, there are many more H+ ions available in the solution due to both the dissociation of sulfuric acid and water.
3. Water Takes Over: On the other hand, at the anode (positive electrode), oxidation occurs. Ideally, OH- ions would be oxidized to form water and oxygen gas (O2). However, in dilute sulfuric acid, the concentration of OH- ions is much lower than H+ ions. Moreover, water itself is a better reducing agent than H+ ions, meaning it's easier for water to lose electrons than for free H+ ions in solution.
4. The Net Effect: As a result, water wins the competition at the anode. Water molecules lose electrons, releasing oxygen gas (O2) and forming OH- ions. These OH- ions then replenish those consumed in the overall reaction. Meanwhile, at the cathode, H+ ions are reduced to hydrogen gas (H2).
Platinum's Role: The platinum electrodes themselves are inert (don't participate in the reaction) and simply serve as conductors for the electricity.
Overall, the electrolysis of dilute sulfuric acid favors the breakdown of water molecules due to their abundance and favorable reduction potential compared to sulfate ions or free H+ ions in solution. This leads to the production of hydrogen gas at the cathode and oxygen gas at the anode.
