Iron (fe) undergoes an allotropic transformation at 912°c: upon heating from a bcc (α phase) to an fcc (γ phase). accompanying this transformation is a change in the atomic radius of fe—from rbcc = 0.12584 nm to rfcc = 0.12894 nm—and, in addition, a change in density (and volume). compute the percentage volume change associated with this reaction. indicate a decreasing volume by a negative number.

  the mississippians were considered to be  horticulturalists, which means they were

Answer asap : ( a. how does mucus prevent the entry of pathogens? b. describe two ways white blood cells protect us from pathogens.

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.