The diagram below shows an area with a trench. Trench
Oceanic crust
Continental crust
Modified from image courtesy of USGS
Which of the following best explains what is happening to the oceanic crust as it is pushed below the continental crust?
OA. The oceanic crust erodes when it collides with the continental crust.
OB. The oceanic crust joins with the continental crust.
OC.
The oceanic crust crystallizes when it dives below the continental crust.
OD.
The oceanic crust melts as it gets pushed below the continental crust.

Which substances have the lowest melting points: ionic covalent, or metallic

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 are the major types of a chemical compound