I have come to answer your lovely chem questions once agai :)

Draw any one of the skeletal structures of a 2° alkyl bromide having the molecular formula of c6h13br and two stereogenic centers. indicate chirality by using wedge and hashed wedge notation. lone pairs do not need to be shown.

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 compounds are the brønsted-lowry bases in this equilibrium: hc2o4– + h2bo3– h3bo3 + c2o42– ? a. h2bo3– and h3bo3 b. hc2o4– and h3bo3 c. hc2o4– and c2o42– d. h2bo3– and c2o42– e. hc2o4– and h2bo3–