Explanation
When you put sand, salt, and sawdust in a glass of water, the following things happen: Salt dissolves in water, meaning it breaks down into individual particles that are distributed evenly throughout the water. Sand sinks to the bottom of the glass, because it is denser than water and cannot float or dissolve in it. Sawdust floats on top of the water, because it is less dense than water and is able to remain suspended on the surface.
