Pb2+(aq) + 2 e- --> Pb(s) Eo = -0.13V Zn2+(aq) + 2 e- --> Zn(s) Eo = -0.76V 9. Given the half-cell potentials above, when the reaction Zn(s) + Pb2+(aq) --> Zn2+(aq) + Pb(s) is made into a voltaic cell, the Ecell is: A. 0.63 V B. -0.63 V C. 0.89 D. 0.89

10. according to the law of conservation of mass, how does the mass of the products in a chemical reaction compare to the mass of the reactants?

A50.0g sample of liquid water at 0.0 c ends up as ice at -20.0 c. how much energy is involved in this change?

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.