Elements+and+the+Periodic+Table

It is useful for us to have a background knowledge of the periodic table because it will help deepen our understanding of materials and their properties. It helps us classify the different elements and we can begin to categorise elements into levels of reactivity. Don’t worry, we don’t have to explicitly know or teach this area, but it will help in understanding the context of some KS2 chemistry. The way the elements are arranged in the periodic table depends on their atomic structure. They are placed in order of atomic number. Each element is presented in a square of the table. Each square contains the symbol of the element, the atomic mass and the atomic number. The atomic mass is the relative mass of the atom. The atomic number is the number of protons that make up the element and is found at the bottom of the square.
 * Elements and the Periodic Table: Background for teaching ‘Materials and Their Properties’**

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The periodic table can be split into rows and columns. The horizontal rows are referred to as ‘periods’ and the vertical columns as ‘groups’. Elements in the same group share similar properties because they have the same number of electrons in their outer shell. The number of the group tells us the number of electrons the elements have in their outer shells. This means that they have similar levels of reactivity as it is the activity of the electrons in the outer shell that determine the degree of the chemical reactions. Group 1 contains the least reactive elements because they only contain 1 electron.

See this link for a basic explanation: @http://www.bbc.co.uk/learningzone/clips/groups-and-periods-in-the-periodic-table/10623.html

This is also a good link for a basic understanding of what we’ve been discussing: @http://www.tes.co.uk/teaching-resource/KS3-4-Science-Periodic-Table-Ferocious-Elements-6047945

[1] @http://www.classzone.com/books/earth_science/terc/content/investigations/es0501/es0501page06.cfm, accessed 28/9/2011.