help me Classify the following substances as:

Pure Substance – P Solution – S Mechanical Mixture – MM
Suspension – SU Colloid - C

Substance

Apple Juice

2005 Penny

Propane

Chicken Noodle Soup

Milk

Salsa

14 Karat Gold Ring

Air

Pepsi (in a glass)

Chocolate Chip Cookie

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.