6 GROUPA vertical column in the periodic table. Also known as the Chemical Family.
7 VALENCE ELECTRONSThe electrons in the outermost energy level of an atom.
8 REACTIVITYHow likely an element is to form compounds with other elements.
9 METALLOIDHave some properties of both metals and nonmetals.
10 NOBLE GASThe elements in Group 18. Also known as the Inert Gases.
11 The Periodic Table Notes p.13 Mendeleev arranged the elements in order of their atomic massesThis arrangement of the elements was the first step in producing a useful scientific tool known as the periodic tableToday, elements are arranged in order of atomic number
12 Periods and Groups Periods numbered from 1 to 7 Elements in each period increase in atomic number moving across the row from left to rightGroups are numbered from 1 to 18.Elements in the same group have similar chemical propertiesThe number and arrangement of valence electrons tells how atoms of one element will combine with atoms of other elements to form compoundsElements in groups 1 and 2 and are the main group elementsElements in Groups 3-12 are called transition elementWith the exception of hydrogen, the elements on the left side of the periodic table are metalsElements on the right side of the periodic table are nonmetals
13 Chemical FamiliesThe most chemically active metals are in Group 1 (alkali metals)Group 2 are called alkaline earth metals, highly reactive but are slightly less reactive and harder than Group 1Group 3 through Group 12 are called Transition elements (hard solids; high melting points)Metalloids: fall along a jagged line on the periodic table between the metals and nonmetals.Noble Gasses: these gases are the least reactive elements.
14 The Periodic Table HW p. 111. Which of the following is the basis for arranging the elements in the modern periodic table?alphabetical order c. number of protonsmass of atoms d. date of discovery2. How many elements are listed in the modern periodic table?a c. 72b d. more than 100
15 3. What do elements in the same column have in common. a 3. What do elements in the same column have in common? a. similar chemical properties b. same number of protons c. same atomic masses d. same size of their atoms