What is the correct size of filter paper for gravity filtration?

The appropriate size of filter paper for gravity filtration should be small enough to sit below the rim of the funnel. This allows for effective filtration while ensuring that the filter paper does not obstruct the flow of the liquid through the funnel. Having the paper sit below the rim prevents any potential overflow of the liquid and maintains a stable environment for filtration.

If the filter paper is too large and reaches or extends over the rim of the funnel, it could interfere with the liquid flow and lead to inefficient filtration. Moreover, having it completely cover the funnel might cause air blockage, preventing the liquid from flowing through properly. Therefore, the ideal size keeps the paper neatly within the boundaries of the funnel, ensuring optimal filtration conditions.