Which two types of waves require matter in order to travel? О A. Light Waves

О B. Water Waves

О C. Electromagnetic Waves

О D. Sound Waves

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.

Scientific evidence tells us that the cause of earths four season is the tilt of earth as it revolves around the sun. the student is instructed to illustrate this information in a science notebook. how will the student illiterate winter in the northern hemisphere?

Percent ionization for a weak acid (ha) is determined by the following formula: percent ionization=[ha] ionized[ha] initial×100%for strong acids, ionization is nearly complete (100%) at most concentrations. however, for weak acids, the percent ionization changes significantly with concentration. the more diluted the acid is, the greater percent ionization.a certain weak acid, ha, has a ka value of 9.4×10? 7.part acalculate the percent ionization of ha in a 0.10 m solution.part bcalculate the percent ionization of ha in a 0.010 m solution