The shielding of electrons gives rise to an effective nuclear charge, zeff, which explains why boron is larger than oxygen. estimate the approximate zeff felt by a valence electron of boron and oxygen, respectively? view available hint(s) the shielding of electrons gives rise to an effective nuclear charge, , which explains why boron is larger than oxygen. estimate the approximate felt by a valence electron of boron and oxygen, respectively? +5 and +8 +3 and +6 +5 and +6 +3 and +8 +1 and +4

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.

The fact that the total amount of energy in a system remains constant is a(n)

Analyze the reaction to determine whether the reaction is exothermic or endothermic. explain your reasoning.