ECS - Exam 2 2025 With Correct
Answers
Sorption - correct answer The retention of a species without the implications to its retention mechanism
o o o o o o o o o o o o o o o
Adsorption - correct answer The binding of an ion or small molecule to a surface at an isolated site (2d-surface
o o o o o o o o o o o o o o o o o o o o
complex). Not including surface precipitation and/or polymerization. One of the most important chemical
o o o o o o o o o o o o o
processes in soils - nutrients, metals, pesticides, and other organic chemicals retained on soil surfaces; affects
o o o o o o o o o o o o o o o o
transport of nutrients and contaminants in soils
o o o o o o
Absorption - correct answer The uptake of a species WITHIN another material
o o o o o o o o o o o
Surface Precipitation - correct answer A 3D growth mechanism of a species on a surface. This mechanism
o o o o o o o o o o o o o o o o o
differs from Adsorb. in that the retained species directly interacts with each other on the surface and can eve
o o o o o o o o o o o o o o o o o o o
have the solid structure grow away from the original substrate
o o o o o o o o o
Precipitation - correct answer The formation of a 3D structure without the association of a substrate (sorbent)
o o o o o o o o o o o o o o o o o
material
Sorptive - correct answer A species in solution that may undergo sorption
o o o o o o o o o o o
Sorbate - correct answer A species retain on another material
o o o o o o o o o
, Sorbent - correct answer The substrate material responsible for the retention of a solution species
o o o o o o o o o o o o o o
Fate of Pesticides - correct answer Drift, photodecomposition, runoff, volatilization, absorption, soil
o o o o o o o o o o o o
decomposition - adsorption, residues, leaching o o o o
Inorganic Surface Function Groups - correct answer Oxygen atoms of the silica tetrahedral layer (siloxane
o o o o o o o o o o o o o o o
surface) in the interlayer region of phyllosilicates. OH groups associate with edges of minerals
o o o o o o o o o o o o o
Surface Functional Groups - correct answer Hydroxyl, Carbonyl (organic), Carboxyl (organic), and Amino
o o o o o o o o o o o o o
Group. Phenolic - consists of phenyl and hydroxyl groups (organic)
o o o o o o o o o
Forces involved in Adsorption - correct answer Physical (distance and valence) - Van der waals (weak
o o o o o o o o o o o o o o o o
electrostatic forces) and Electrostatic complexes (ion exchange)
o o o o o o
Chemical (electron reconfiguration, breaking/making bonds)- Inner-sphere and outer-sphere complexation
o o o o o o o o
Surface Complex - correct answer Surface Function Group + ion or molecule in solution = stable molecular
o o o o o o o o o o o o o o o o o
entity, called SURFACE COMPLEX
o o o
Surface Complexes - correct answer Outer-sphere - water molecule is present between the SFG and bound
o o o o o o o o o o o o o o o o
(adsorbed) ion or molecule. o o o o
Inner-sphere complex - no water molecule present between the SFG and bound ion or molecule
o o o o o o o o o o o o o o
Inner and outer-sphere complexation occurs simultaneously (not mutually exclusive)
o o o o o o o o
Inner-sphere Complex - correct answer Strong (covalent and ionic bonding), May be slower than outer sphere
o o o o o o o o o o o o o o o o
complexation, Often irreversible or "fixed" depending upon environmental conditions, weakly affected by
o o o o o o o o o o o o
solution ionic strength, surface charge can be changed by complexation, charged surface is not required for
o o o o o o o o o o o o o o o o
complexation
Answers
Sorption - correct answer The retention of a species without the implications to its retention mechanism
o o o o o o o o o o o o o o o
Adsorption - correct answer The binding of an ion or small molecule to a surface at an isolated site (2d-surface
o o o o o o o o o o o o o o o o o o o o
complex). Not including surface precipitation and/or polymerization. One of the most important chemical
o o o o o o o o o o o o o
processes in soils - nutrients, metals, pesticides, and other organic chemicals retained on soil surfaces; affects
o o o o o o o o o o o o o o o o
transport of nutrients and contaminants in soils
o o o o o o
Absorption - correct answer The uptake of a species WITHIN another material
o o o o o o o o o o o
Surface Precipitation - correct answer A 3D growth mechanism of a species on a surface. This mechanism
o o o o o o o o o o o o o o o o o
differs from Adsorb. in that the retained species directly interacts with each other on the surface and can eve
o o o o o o o o o o o o o o o o o o o
have the solid structure grow away from the original substrate
o o o o o o o o o
Precipitation - correct answer The formation of a 3D structure without the association of a substrate (sorbent)
o o o o o o o o o o o o o o o o o
material
Sorptive - correct answer A species in solution that may undergo sorption
o o o o o o o o o o o
Sorbate - correct answer A species retain on another material
o o o o o o o o o
, Sorbent - correct answer The substrate material responsible for the retention of a solution species
o o o o o o o o o o o o o o
Fate of Pesticides - correct answer Drift, photodecomposition, runoff, volatilization, absorption, soil
o o o o o o o o o o o o
decomposition - adsorption, residues, leaching o o o o
Inorganic Surface Function Groups - correct answer Oxygen atoms of the silica tetrahedral layer (siloxane
o o o o o o o o o o o o o o o
surface) in the interlayer region of phyllosilicates. OH groups associate with edges of minerals
o o o o o o o o o o o o o
Surface Functional Groups - correct answer Hydroxyl, Carbonyl (organic), Carboxyl (organic), and Amino
o o o o o o o o o o o o o
Group. Phenolic - consists of phenyl and hydroxyl groups (organic)
o o o o o o o o o
Forces involved in Adsorption - correct answer Physical (distance and valence) - Van der waals (weak
o o o o o o o o o o o o o o o o
electrostatic forces) and Electrostatic complexes (ion exchange)
o o o o o o
Chemical (electron reconfiguration, breaking/making bonds)- Inner-sphere and outer-sphere complexation
o o o o o o o o
Surface Complex - correct answer Surface Function Group + ion or molecule in solution = stable molecular
o o o o o o o o o o o o o o o o o
entity, called SURFACE COMPLEX
o o o
Surface Complexes - correct answer Outer-sphere - water molecule is present between the SFG and bound
o o o o o o o o o o o o o o o o
(adsorbed) ion or molecule. o o o o
Inner-sphere complex - no water molecule present between the SFG and bound ion or molecule
o o o o o o o o o o o o o o
Inner and outer-sphere complexation occurs simultaneously (not mutually exclusive)
o o o o o o o o
Inner-sphere Complex - correct answer Strong (covalent and ionic bonding), May be slower than outer sphere
o o o o o o o o o o o o o o o o
complexation, Often irreversible or "fixed" depending upon environmental conditions, weakly affected by
o o o o o o o o o o o o
solution ionic strength, surface charge can be changed by complexation, charged surface is not required for
o o o o o o o o o o o o o o o o
complexation
