Biology – 3.1 Diffusion | e-Consult

1. The dye spread across the filter paper because of diffusion. The dye molecules moved from the area of higher concentration (the drop of dye) to the area of lower concentration (the rest of the filter paper) until the dye was evenly distributed.

2. If the filter paper was heated, the rate of diffusion of the dye would increase. Heating the filter paper increases the kinetic energy of the dye molecules. This means they will move faster and diffuse more quickly across the paper. A higher temperature also reduces the viscosity of the filter paper, making it easier for the dye molecules to move through it.