Thermal Expansion - due to daily changes in temperature, specially great in hot dry desert areas. Organic Activity - plant roots, burrowing animals, man. B. Chemical Weathering Changes the internal structures of minerals by removing or adding elements. The orginal rock decomposes that or in equilibrium or in the balance or stable with the environment at the surface. Rocks and minerals changes as a response to changing environment.
Water turns to ice when it cools below freezing.
Lead melts to liquid when temperature is increased. Minerals were formed under conditions of high temperature and pressure. Solution - dissolution of some minerals in the rock will weaken the rock. Although water molecules are electrically neutral, they have a positive and a negative end. Many minerals are insoluble in H 2 O, but with the addition of weak acids, they dissolve easily.