Why is the indifferent electrode larger than the needle in galvanic electrolysis?

The larger size of the indifferent electrode in galvanic electrolysis is primarily to minimize the effect of chemical compounds deposited during the electrolysis process. The indifferent electrode serves to disperse the electrical current over a wider area, which helps to reduce localized chemical reactions that would otherwise occur around a smaller electrode. By ensuring that the current is spread out more, there is a lower concentration of chemical byproducts at any single point, thereby minimizing irritation to the surrounding skin and potential adverse effects. This design consideration is crucial for maintaining skin health and enhancing the overall effectiveness of the electrolysis treatment.