The Bohr Model of atom is a planetary model in which the negatively charged electrons orbit a small, positively charged nucleus similar to the planets orbiting the sun.
A True
B False

Asample of the male sex hormone testosterone, c19h28o2, contains 3.88×10^21 atoms of hydrogen.(a) how many atoms of carbon does it contain? (b) how many molecules of testosterone does it contain? (c) how many moles of testosterone does it contain? (d) what is the mass of this sample in grams?

A3.37-mg sample of protein was chemically digested to convert its nitrogen into ammonia and then diluted to 100.0 ml. then 10.0 ml of this solution was placed in a 50-ml volumetric flask and treated with 5 ml of phenol solution plus 2 ml of sodium hypochlorite solution. the sample was diluted to 50.0 ml, and the absorbance at 625 nm was measured in a 1.00-cm cuvette and found to be 0.486. for reference, a standard solution was prepared from 10.0 mg of nh4cl (molar mass = 53.49 grams/mole) dissolved in 1.00 l of water. then 10.0 ml of this standard was placed in a 50-ml volumetric flask, treated in the same manner as the unknown, and the absorbance found to be 0.323. finally, a reagent blank was prepared using distilled water in place of unknown, it was treated in the same manner as the unknown, and the absorbance found to be 0.076. calculate the weight percent of nitrogen in the protein.

Will give ! what are the advantages and disadvantages of nuclear power? check all that apply. one advantage of nuclear energy is that it does not produce carbon dioxide emissions. storage of nuclear waste is a short-term problem associated with nuclear energy. the problem with uranium mining is that a large quantity of uranium must be extracted to meet energy needs because the energy release from uranium fission is so low. safe operation of a nuclear power plant can be jeopardized by a human mistake.