1. The Arrangement of Elements in the Periodic Table Trends in the Periodic Table and Bonding

2. The Periodic Table The periodic table is a very useful arrangement of all of the known chemical elements. It can be used to observe patterns and relationships between different elements, and the table is arranged in several important ways.

3. Periods Horizontal rows in the periodic table are called periods. Elements are arranged in the periodic table in order of increasing atomic number. Li 3 Be 4 B 5 C 6 N 7 O 8 F 9 Ne 10 The outer electron shell becomes filled as we move from left to right. Li 2,1 Be 2,2 B 2,3 C 2,4 N 2,5 O 2,6 F 2,7 Ne 2,8 The atomic number of the elements increases by one moving left to right along a period.

4. METALS NON- METALS Metals and Non-Metals We can divide the periodic table with a staircase line to show elements that are metals and non-metals. As we move along a period from left to right we see a shift from metal to non-metal characteristics.

5. Numbered vertical columns of elements in the periodic table are called groups. Groups 1234567012345670

6. Some groups are known by special names Alkali Metals Transition Metals Halogens Noble Gases 12345670

7. 13456702 Elements in the same group have similar chemical properties The alkali metals are all soft, very reactive metals. Li 3 Na 11 K 19 Rb 37 Cs 55 They all have one electron in their outer shell and show a gradual trend in both chemical and physical properties as we move down the group 1

8. 13456702 Elements in the same group have similar chemical properties The halogens are all very reactive non-metal elements. They all have seven electrons in their outer shell. The halogens are the only group to contain all three states of matter at room temperature. F 9 Cl 17 Br 35 I 53 At 85 7

9. 13456702 Elements in the same group have similar chemical properties The noble gases are all unreactive gaseous elements. He 2 Ne 10 Ar 18 Kr 36 Xe 54 They all have a full outer electron shell and are all odourless, colourless monatomic gases. Rn 86 0