While the diffusion process is always faster at higher temperatures, we can write differents states of matter in the first two blanks, and the sentence would still be true. Diffusion is faster the less packed is the state of matter.
Thus, these are some of the possibilities:
- All substances diffuse faster in liquids than in solids and at higher temperatures.
- All substances diffuse faster in liquids than in gels and at higher temperatures.
- All substances diffuse faster in gels than in solids and at higher temperatures.