Answers: 3
Chemistry, 22.06.2019 05:30
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.
Answers: 1
Chemistry, 22.06.2019 14:10
16. in a reaction that has reached equilibrium, a. the forward and reverse reactions are occurring at the same rate. b. the reactants and products are in equal concentrations. c. the forward reaction has gone further than the reverse reaction. d. there are equal numbers of atoms on both sides of the equation. e. a, b, and d are correct.
Answers: 2
Chemistry, 22.06.2019 18:30
The famous scientist galileo galilei did several experiments with sloping planes, which he rolled metal balls down so that he could study motion. by changing the slope, he could study how the speed at which the ball rolled was affected. what was the independent variable in galileo's experiment? a. the speed of the ball b. the slope of the plane c. whether the ball moved d. what the ball was made of
Answers: 2
Chemistry, 23.06.2019 09:00
20 grams of water. she poured out 15 grams. which of the following physical properties of the water changes? a .boiling point b. density c .electrical conductivity d .volume
Answers: 2
A student is heating a chemical in a beaker with a Bunsen burner. In a paragraph of at least 150 wor...
Mathematics, 11.02.2021 07:50
Mathematics, 11.02.2021 07:50
Chemistry, 11.02.2021 07:50
Mathematics, 11.02.2021 07:50
Social Studies, 11.02.2021 07:50
Business, 11.02.2021 07:50
Social Studies, 11.02.2021 07:50
Mathematics, 11.02.2021 07:50
Mathematics, 11.02.2021 07:50