Suppose three different people take measurements of the height of a skateboard ramp. The three measurements are 27.4 cm, 27.5 cm, and 27.5 cm. The actual height of the ramp is 30.5 cm. Which of the following best describes these results? A) Both accurate and precise B) Precise but not accurate C) Neither accurate nor precise D) Accurate but not precise

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 effect might melting sea ice have for people who live in coastal areas?

How many atoms are there in 5.70 mol of mg