Acompound contains only carbon, hydrogen, nitrogen, and oxygen. combustion of 0.157g of the compound produced 0.213g of co2 and 0.0310g of h2o. in another experiment, it is found that 0.103g of the compound produces 0.0230g of nh3. what is the empirical formula of the compound?

Covalent network solids typically have melting points and boiling points. the chemical formula of a network solid indicates in the molecule.

Find the number of moles of argon in 364g of argon.

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.