About 40 different substances called organophosphorus compounds are registered in the united states as insecticides. they are considered less damaging to the environment than some other insecticides because they breakdown relatively rapidly in the environment. the first of these organophosphorus insecticides to be produced was tetraethyl pyrophosphate, tepp, which is 33.11% carbon, 6.95% hydrogen, 38.59% oxygen, and 21.35% phosphorus. it has a molecular mass of 290.190. what is the molecular formula for tepp?

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.