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Over the course of soil development from parent rock to highly weathered soils, mineral weathering reactions occur that alter the surface chemistry of the soil.  Consider the weathering transformation sequence: muscovite/biotite → illite → vermiculite → smectite → kaolinite → gibbsite During the above weathering sequence, what general changes would be expected in following mineral chemical characteristics? Why? (a)  Permanent (structural) charge (b)  pH dependent (variable) charge (c)  Types of surface functional groups (d)  Cation exchange capacity (e)  Anion exchange capacity

A water sample is found to contain Cu but no organic or inorganic ligands except OH-. Assume that only one hydrolysis species contributes significantly to the total Cu in solution.          K        log Kf Cu2++H2O⇌Cu(OH)++H+{“version”:”1.1″,”math”:”Cu2++H2O⇌Cu(OH)++H+”} 10-7.52 -7.52    If [Cutotal] = 10-{T} M and pH = {pH}, what is the concentration of free Cu2+ in the water sample?  Format answer in scientific notation and round to 3 significant figures. Place the order of magnitude (x10^y) in the “units” box with no spaces (D2L doesn’t have a separate spot for this), followed by the units. For example: x10^-4 mol/L.

Water found in the pores of a soil has the following properties: Negligible ionic strength (activity = concentration) a constant pH of {pH} (Ca2+) = 10{Ca} M total P = 10{P} M Given the dissolution reaction of brushite is written: CaHPO4·2H2O(s)   +  H+ (aq)  ⇄   Ca2+(aq) +  H2PO4– (aq) +  2H2O   …and that H3PO4 has a pKa2 of 7.21, calculate log(IAP) (same as log(Q)) of the reaction, and save your answer for the next question.

Which of the following images shown below demonstrates the correct way to place a lateral view of the canine elbow onto the screen for evaluation by your clinician? Assume that the R marker in each image is placed correctly. To answer this question, select A, B, C, or D. A.   B.   C.   D.

You are evaluating a radiograph like the one shown in the image below for mAs and kVp. You see that the image is overall too dark. You cannot see the structures within the abdomen at all. The lumbar vertebra, ribs, and pelvis are visible but appear darker than they should.  The density of air and the density of the metal marker are appropriate.  Which of the following adjustments do you need to make to improve the radiograph technique for this image?

Rate how strongly you agree or disagree with the following statement: “I feel prepared to explain how chemical composition of organic and inorganic components of soil and water bodies influence chemical processes therein”

You are evaluating a radiograph like the one shown in the image below for mAs and kVp.  The radiograph appears overall too dark.  The anatomy of interest appears to be adequately penetrated by the x-rays.  The radiographic density of the air on the radiograph appears dark gray but not black.   Which of the following adjustments should you make to improve this radiograph?

The below questions are bonus feedback questions Did you have enough time to complete this exam?

Do you have any other feedback for this course?

Rate how strongly you agree or disagree with the following statement: “I feel prepared to recommend appropriate techniques for analyzing specific chemical properties of soils and natural water bodies”