Some soil colloids exhibit positive charges under highly acid conditions. To what are these charges likely due?
A) the release of some OH- ions leaving an unsatisfied positive charge on the colloid
B) the adsorption of Al3+ ions on the colloid
C) protonation of some hydroxy groups by excess H+ ions
D) increase in the level of H+ ions on the exchange complex
E) substitution of lower valent atoms for higher valent atoms in the octahedral sheet
C
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Abrasive grinding is more easily accomplished on ____ materials.?
A. ?thermoplastic B. ?foamed C. ?thermosetting D. ?laminate
Why must condensate pumps used with condensing furnaces be approved for furnace condensate use?
A) The condensate from a furnace is mildly acidic and can damage the materials in some condensate pumps B) The furnace manufacturer will void the warranty if the wrong condensate pump is used C) The condensate from a furnace is mildly alkaline and can damage the materials in some condensate pumps D) The condensate from a furnace is flammable and only furnace rated condensate pumps can pump flammable liquid
Computer-aided drafting, or CAD, is now the norm in the modern structural engineering department. Which of the following statements helps explain this practice?
A. Not only has CAD simplified the issue of engineering lettering, it also allows each technician to express a great deal of individual creativity. B. CAD drawings include many choices for paper sizes, thus, the standard sizes B, C, and D, are used much less frequently. C. The use of scales is much easier with CAD systems since the scale is selected before beginning the drawing. D. The consistent quality of the linework and lettering is much improved in CAD systems as compared to hand drawings.
If some root other than a square root is to be found, a small number is placed outside the radical sign. This number indicates what root is to be found.
Answer the following statement true (T) or false (F)