Particles of the substance have the most kinetic energy when the substance is(a)1. A gas. The part of the graph that represents where the substance has the least amount of potential energy is labeled(b)1. Solid.
Gas molecules have the highest average velocities among the three states of matter so gas has the highest kinetic energy. During freezing, a substance loses a lot of potential energy so solid has the least potential energy.
Most rocks that we encounter in our normal everyday lives are sedimentary rocks. Sedimentary rocks are rocks that have been worn down gradually over long periods of time. Because it takes very long periods of time (couple decades) for these rocks to change, it often seems as if they don't change at all, when in reality the change is too small for us to realize it!
