What is the pOH of a solution with a pH of 6.38?

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.

What is the average rate of the reaction between 10 and 20 s?

Many bird species build nests in which they raise their offspring. one of these species is known as the magnolia warbler. breeding pairs of magnolia warblers build nests out of pieces of grass and twigs. the female warbler will then lay her eggs in the nest and sit on the eggs for a few weeks until they hatch. after the offspring have hatched, the female will continue to sit on the newborn chicks to keep them warm. both the male and the female bring food for the offspring to eat until the young are mature enough to find food on their own. which of these most likely describes why birds such as the magnolia warbler build nests in which to raise their offspring? a. nest building decreases the amount of energy used by the parent birds to raise their offspring to adulthood. b. nest building increases the probability that the offspring will survive and eventually produce offspring of their own. c. nest building decreases the amount of food that the offspring require the adult birds to provide. d. nest building increases the probability of the offspring being located by airborne predators.