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What is the molarity of a solution that is prepared by adding 57.1 g of toluene (c 7 h 8 ) (density = 0.867 g/ml) to a 250 ml volumetric flask, and then filling to the mark with benzene (c 6 h 6 ) (density = 0.876 g/ml)?

Tooth enamel consists mainly of the mineral calcium hydroxyapatite, ca_10(po_4)_6(oh)_2. trace elements in teeth of archaeological specimens provide anthropologist with clues about diet and diseases of ancient people. students at hamline university measured strontium in enamel from extracted wisdom teeth by atomic absorption spectroscopy. solutions with a constant total volume of 10.0 ml contained 0.726 mg of dissolved tooth enamel plus variable concentrations of added sr. added sr find the concentration of sr in the 10 ml sample solution in parts per billion = ng/ml. find the concentration of sr in tooth enamel in parts per million = mu g/g.

Which statement best summarizes the importance of ernest rutherford’s gold foil experiment? it proved that all of john dalton’s postulates were true. it verified j. j. thomson’s work on the atomic structure. it showed that an electron circles a nucleus in a fixed-energy orbit. it showed that a nucleus occupies a small part of the whole atom.