Question

can a liquid substance diffuse in another liquid substance

Answer 1

Yes
Diffusion is mainly gases property
Diffusion is shown also by liquids but much less than the gases
Liquids diffuse from solutions of higher concentration to solutions of lower concentration
So the driving force for the diffusion is concentration difference.
Rate of Diffusion depends on liquid`s viscosity,temperature etc.
depends on what is the liquid however. (oil and water dont)

examples
food coloring in water. liquid chocolate in milk.

Read more: http://wiki.answers.com/Q/Can_A_liquid_can_be_diffused_into_another_liquid#ixzz24fEG0qrH

Answer 2

Absolutely! When you drop food coloring disperse inside water that's a form of diffusion.

Answer 3

can water diffuse to another water :) ?

diffusion vs osmosis