In reaction a, each sodium atom gives one electron to a chlorine atom in reaction be an isotope of oxygen decays to form an isotope of nitrogen. Which statement best describes the energy that is released per gram by these reactions

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.

Draw metallic bonding if two copper

One similarity and one difference between an element and a mixture of elements