g A compound is decomposed in the laboratory and produces 4.20 g N and 0.30 g H. What is the empirical formula of the compound

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

The grooves or folds of the brain are called

Chen drew a diagram to compare the ways in which different organisms obtain nitrogen. which label belongs to the area marked z?