When discussing the periodic table whole groups are often talked about. This is also how you sit. When you do assignments together your answers are often similar... but not the same. The periodic table is organized the same way. When finished here you should be able to: use the Periodic Table to identify and explain the properties of chemical families, including alkali metals, alkaline earth metals, halogens, noble gases, and transition metals. Our focus will mainly be on the representative groups, those that are highest on the periodic table and have their group numbers labeled with "A."
We also often compare groups to each other, and elements within a group when trying to do different things such as substitute an element in a reaction in an attempt to make the final product cheaper. Doing this is called comparing trends and you should be able to: use the Periodic Table to identify and explain periodic trends, including atomic and ionic radii, electronegativity, and ionization energy. You should also be able to predict the charge/oxidation state for each element.
Atomic Radius - the distance from the nucleus to the outer most electron. Here the trend is that atoms get larger down a family and left across a period.
Electronegativity is the strength of attraction to an electron. Here, if a free electron is moving about it is most likely to go to Fluorine. The trend is electronegativity gets stronger up a family and right across a period. EXCEPTION: NOBLE GASSES. Their energy levels are already full as shown in their Bohr diagrams.
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Ion size - the relative size when electrons are transferred to or from an atom to become an ion. Here it is shown that metals get smaller (donate electrons) and non-metals get larger (gain electrons). This electron movement also gives the atoms "CHARGES" which is what makes them ions.
Ionization energy is the amount of energy it takes to REMOVE an electron and make the atom an ion. Notice that metals are quite easy to remove electrons from, and non-metals are extremely difficult. This explains the Ion size diagram above. The trend is increasing up a family, and right across a period.
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These are the common "charges" that atoms of a particular group take. Transition metals play by different rules as we'll see later, so I have to give you their charge with a Roman Numeral in their name. Commonly you will see I = 1, II = 2, III = 3 and IV = 4. Group 14 is another exception to the rule, not shown in the picture above is that Carbon and Silicon, being non-metals actually get a 4- charge as opposed to the metals that make up the rest of the group (Ge, Sn, Pb get +).