Mendeleev lined up the cards in order of increasing mass. Mendeleev’s Periodic Table
The Calendar Like the calendar, today’s Periodic Table is organized in rows and columns.
The Periodic Table Today TODAY: Elements are organized into rows and columns based on their atomic number. Or Family
Periods: The ROWS in the Periodic Table. The atomic number increases. Period 1 Period 3 Period 4 Period 5 Period 6 Period 7 Period 2 Period 7 Period 6
Why are some of the elements in periods 6 and 7 moved below?
Groups: The Columns in the Periodic Table share common properties. Group 1 Group 2 Group 3Group 4Group 5Group 6Group 7Group 8Group 9Group 10Group 11Group 12 Group 13Group 14Group 15Group 16 Group 17 Group 18
Finding Data on Elements Each square in the periodic table lists four pieces of information: an element’s atomic number, chemical symbol, name, and atomic mass.
What is the Atomic Number? The atomic number represents the number of PROTONS in the element.
Types of Elements There are 3 types of elements in the Periodic Table: METALS SEMIMETALS (Metalloids) NON-METALS
METALS & Semimetals Metals are good conductors, and almost all are solids at room temperature. Semimetals are elements that have some of the same properties of metals and nonmetals. The most important property of the semimetals is their varying ability to conduct electricity. One of the most common semimetal is Silicon (Si) used in semiconductor production.
Nonmetals Nonmetals are elements that lack most of the properties of metals. Many are gases at room temperature. Most form compounds so they are very reactive (except group 18). They are poor conductors and are brittle.