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5 Which of the following is an example of the Law of Conservation of Mass?
(A) slowly eating an ice cream to make it last as long as possible
(B) wind rustles leaves in a tree
(C) a cup of ice melts and liquid water remains
(D) someone picks up trash in their neighborhood

The small bags of silica gel you often see in a new shoe box are placed there to control humidity. despite its name, silica gel is a solid. it is a chemically inert, highly porous, amorphous form of sio2. because water vapor readily adsorbs onto the surface of silica gel, it acts as a desiccant. despite not knowing mechanistic details of the adsorption of water onto silica gel, from the information provided you should be able to make an educated guess about the thermodynamic characteristics of the process. predict the signs for δg, δh, and δs for the adsorption of water.