How does surface area affect dissolving?
Some things: Agitation: As in, the number of collisions within the molecules. This is why we stir when we are dissolving something.. more collision will increase rate. Temperature: The higher the temperature, the more energy the solution will have, hence more space between the molecules because they move around so much. This means more kinetic energy. Surface area: Meaning the area of contact within the solute and the solvent. More surface area = faster dissolving.
The actual surface area of the substance is larger when it's in powdered form, and as dissolving only happens at the surface area, dissolving a powder is a faster process. It is not an absolute necessity , though. When the substance is not powdered, it will dissolve as well, as the amount you can dissolve is only dependent on the substance involved. However, in powdered form, it will dissolve quicker.