When matter is broken down physically by wind or chemically by salt water, what is
this known as

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.

it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added