What effect does grinding a solid into a powder have on its chemical reactivity?

Grinding a solid into a powder significantly increases its reactivity primarily because it increases the surface area. When a solid material is powdered, the smaller particle size means there is more surface area available for reactions to occur. This enhanced surface area allows for more frequent and effective collisions between reactant particles, which is essential for chemical reactions to take place.

In a powdered form, the particles are more dispersed, enabling them to interact with other substances more readily than they would in a larger, intact form. This is why processes like combustion, corrosion, and many other chemical reactions proceed more rapidly with finely ground solids than with larger chunks of the same material, supporting the notion that grinding a solid indeed facilitates increased chemical reactivity.