Which of the following pair will exhibit diffusion?
Tea in tea bag and hot water
Diffusion is defined as the movement of the molecules from the region of higher concentration to the region of lower concentration. So because of the concentration difference, molecules start to move.
There are lots of tea molecules in the bag and none outside. Now the addition of heat from hot water to the tea bag causes its molecules to move much faster than at room temperature from the region of higher to lower concentration.