A200.0ml flask of unknown gas was placed in a hot water bath. the temperature of the bath was found to be 99 degrees c. the pressure of the flask was 733mmhg. the flask with the unknown gas in it had a mass of 126.593g. the same flask weighed 125.623g when it was empty. determine the mass f the unknown gas in the flask. determine the molar mass of an unknown gas. (assume that the ideal gas law is obeyed and use r= 0.0821 l atm/mol k show all work.)

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.