Key Concepts

Periodic Table Basics

 The periodic table is a table of all the elements which make up  Elements initially grouped in a table by  Symbols – each element has a symbol which is either a Capital Letter or a Capital Letter followed by a lower case letter  – the number above an element’s symbol which shows the number of – the number found below an elements symbol which shows the mass of the element. Mass = the number of protons + the number of – the elements which have the properties of malleability, luster, and conductivity o These elements are good conductors of electricity & heat. o Found to the left of the zig-zag line on the periodic table  – do not have the properties of metals. Found to the right of the zig-zag line  – elements found along the zig-zag line of the periodic table and have some properties of metals and nonmetals (B, Si, Ge, As, Sb, Te, and Po) Groups

 The columns going up and down (There are 18 groups)  1: , , , , , Cesium, and  Elements arranged so that elements with similar properties would be in the same group. o Group 1 Metals - highly reactive metals o Group 2 Alkali Metals – reactive metals o Group 3-12 Transition Metals o Group 17 – highly reactive non-metals o Group 18 Noble - do not react or combine with any other elements.  Elements are grouped according to their properties or  Reactivity is determined by the number of in an element’s outer level  These electrons are called electrons Periods

 The rows that run from left to right on the periodic table (There are 7 periods)  1 contains 2 elements, Hydrogen and .  Period 2 contains 8 elements: Lithium, , , , , , ,  The different periods represent different energy levels. o Elements in period 1 have electrons in just one energy level. o Elements in period 2 have electrons within two different energy levels.

 Metallic properties – the properties that define a tend to increase going to the left and down on the periodic table (malleability, luster, and conductivity)  Atomic mass – increases going to the right and down on the periodic table  – increases going down on the periodic table Periodic Table Key Concepts