Any fluid.
The concentration gradient determines the direction in which a substance diffuses across a membrane. The concentration gradient is a measure of how the concentration of a substance changes from one place to another.
Diffusion
the process in which one object, or substance is take from one place to another
yes,sound waves always move from one substance to another
This reaction is called fermentation.
The process is called metabolism.
the direct transfer of heat from one substance to another substance that it is touching is called
Its the change of one substance into another substance.
A centrifuge.
A substance floats over another substance if it is less dense. Density is a measure of how much mass is in a given volume, so if one substance is less dense than another, it will float on top. This is due to the buoyant force exerted on the less dense substance by the denser substance.
A solution is a mixture in which substance dissolves another one.
No. Evaporation is a physical process and it does not distinguish one substance from another.