This chapter describes the experiments that led to the discovery of the elementary particles that make up the structure of the atom. The fact is stressed that the number of protons determines the identity of an element. The position of the electrons is described in terms of regions around the nucleus. You will learn about isotopes and how to calculate atomic masses. In the last section of the chapter, the periodic table is introduced and you will learn to identify the position of groups, periods, and transition metals in the table.

In this chapter, you will learn: to summarize Dalton's atomic theory to describe the size of an atom to distinguish among protons, electrons, and neutrons to explain how the atomic number identifies an element to calculate the average atomic mass of an element from isotope data to identify the positions of groups, periods, and transition metals in the periodic table