How long does it take to form bauxite (8 points)? australia is the world's largest producer of bauxite, an al ore with an overall composition that can be generalized as al(oh)3. bauxite forms in the tropics, from the intense weathering of granitic rocks. this intense weathering is a soil formation process known as laterization. for this activity, practice your new knowledge of solubility to address the question of how much water needs to pass through the soil to form a laterite. using several unit conversions and our solubility equations, we can calculate the minimum amount of water that needed to pass over these rocks, by assuming that the soil water becomes saturated with the elements that ultimately wash out of the soil (saturation is rarely the case, so consider this when you write up your answer). one element that must wash out of the rock is silica. silica constitutes about 70% of granitic rocks, but its concentration is reduced by~15 times during laterization. we can quantify the solubility of silica as k = a hso-s/hso-1 = 10-2.7 mol l-1 (for now assume that this is independent ofph) this will give you the amount of water (preferred unit is probably liters) needed to reduce, by a factor of 15, the concentration of silica from a given amount of rock. for this exercise we will assume that our bauxite is 30 meters thick (you will probably want to model this a single column of rock that is 30 meters by 1 meter, by 1 meter). you will need to convert to grams of rock and assume a density of 2.5 g/cm. you can then use our solubility equations to calculate the liters of water needed to remove the silica from this column of water if you then convert your results to cubic meters of water (1 liter-0.001 m3) and make reasonable assumptions about precipitation and infiltration rates, you can also make an approximation about soil formation rate. therefore, set up your model in terms of cubic meters of water (1 liter-0.001 m) additional aspect (2 points; just answer in -3-5 sentences) we have a sample of bauxite in the tsv rock garden. it has unusually high radioactivity (as measured by our gamma counter). the major gamma emitters in the crust are k, u, and th. use the solubility constants for u, th, and k listed below and your knowledge from above to comment on: 1) what element is responsible for the radioactivity, and 2) why the rock is unusually radioactive? k for u compounds 10 mol l k for th compounds 101 mol l k for kcl 340 g/l