Compare the effusion rate of O2 and CO2 gas; which one is faster and by how much? 3. What is the total pressure in a scuba tank containing 225 KPa of O2 and 55 KPa of N2 and 22 KPa of He gases-
4. The atmosphere consists mostly of N2, O2, and Ar gases. If atmospheric pressure is 101 KPa at Aztec then find O2 pressure if N2 is 80.8 KPa and Ar is 1.0 KPa-

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.