all show similar chemical behavior and so are listed vertically, as a “family” of elements.A family of elements with similar chemical properties that lie in the same vertical column on the periodic table is called a group. Groups are often referred to by the number over the column (see Fig. 4.9). Note that the group numbers are accompanied by the letter A on the periodic table in Fig. 4.9. For simplicity we will delete the A’s when we refer to groups in the text. Many of the groups have special names. For example, the first column of elements (Group 1) has the name alkali metals. The Group 2 elements are called the alkaline earth metals, the Group 7 elements are the halogens, and the elements in Group 8 are called the noble gases. A large collection of elements that spans many vertical columns consists of the transition metals. ◀Most of the elements are metals. Metals have the following characteristic physical properties: ◀Physical Properties of Metals1. Efficient conduction of heat and electricity2. Malleability (they can be hammered into thin sheets)3. Ductility (they can be pulled into wires)4. A lustrous (shiny) appearance