(3)The Nuclear Atom (15 min) (4)Chemical Elements (15 min) Lecture 2: (5)Atomic Mass (10 min) (6)Introduction to the Periodic Table (15 min) (7)The Concept of the Mole and the Avogadro Constant (15 min) (8)Using the Mole Concept in Calculations (10 min) 三、教学重点与难点 1.教学重点 (1)The historical path leading to identification of atomic structure (2)Mass number,atomic number,neutron number,and atomic mass of an atom (3)Trends in periods and groups (4)Definition of mole and Avogadro's number(3) The Nuclear Atom (15 min) (4) Chemical Elements (15 min) Lecture 2: (5) Atomic Mass (10 min) (6) Introduction to the Periodic Table (15 min) (7) The Concept of the Mole and the Avogadro Constant (15 min) (8) Using the Mole Concept in Calculations (10 min) 三、教学重点与难点 1．教学重点 (1) The historical path leading to identification of atomic structure (2) Mass number, atomic number, neutron number, and atomic mass of an atom (3) Trends in periods and groups (4) Definition of mole and Avogadro’s number