ORGANIZING THE ELEMENTS
* Explain how elements are organized in a periodic table * Compare early and modern periodic tables
* Identify three broad classes of elements
* periodic law
Part A Completion
Use this completion exercise to check your understanding of the concepts and terms that are introduced in this section. Each blank can be completed with a term, short phrase, or number.
Chemists used the _______ of elements to sort them into groups. The periodic table organizes the elements into vertical _______ and horizontal _______ in order of increasing _______. The table is constructed so that elements that have similar chemical properties are in the same _______. _______ have a high luster, or sheen, when cut. Most nonmetals are _______ at room temperature. Elements with properties that are similar to those of metals and nonmetals are called _______. Across the periodic table, the properties of elements become _______ metallic and _______ nonmetallic.
Name Date Class
Part B True-False
Classify each of these statements as always true, AT; sometimes true, ST; or never true, NT.
10. In his periodic table, Mendeleev arranged the elements in order of atomic number.
11. There are six periods in a periodic table.
12. Most of the elements in the periodic table are metals.
13. The elements within a period have similar properties.
Part C Matching
Match each description in Column B to the correct term in Column A.
a. a vertical column of elements in the periodic table
b. good conductors of heat and electric current