Atoms, valence and everything

Valence Electrons

• The valence electrons are the electrons on the outer-most shell of the atom.
• As we can see, Hydrogen only has one shell, which means that is also its valence shell with 1 electron.
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Core Charge

• - The attractive forces the valence electrons receive from the protons, that are in the nucleus.
• - Core Charge = No. Of Protons - Inner shell electrons.
• - An example could be Magnesium. We have 12 protons taking away the 10 inner shell electrons to give us a core charge of +2.
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Electronegativity

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• - The electronegativity, is how strongly an atom attracts electrons. Though note this excludes the noble gasses, as they are most stable with their octet configuration, meaning they have 8 valence electrons.
• - As we can see, the higher the group number, the higher electronegativity, the lower the period number also results in higher electronegativity