TRENDS
IONIC RADIUS
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Ionic radius: the size of a positive or negative ion that is determined by the addition or subtraction of electrons.
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The ionic radius increases towards francium and decreases as you go to the left across the periods.
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Since metals usually lose one or more electrons, they form positive ions. This means that the ionic radii of metal cation (positively charged ion) decreases because it increases its nuclear charge. The nonmentals gain electrons to form anions (negatively charged ions). This would also increase the nuclear charge and decrease the ionic radii.
ATOMIC RADIUS
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Atomic radius: the size of the atomic species as determined by the boundaries of the valence electron.
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The atomic radius increases as you go up on the periodic table (or decreases as you go down). The radius also increases to the left of the table, while decreasing as it moves to the right of the table. This is due to protons and electrons attracting each other and making the radius smaller.
IONIZATION ENERGY
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Ionization energy: the amount of energy required to remove an electron from an atom or ion.
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The ionization energy increases when you move closer to hydrogen (decreasing when you move more towards francium) and increases to the right (decreasing the more you move the the left).
ELECTRONEGATIVITY/ ELECTRON AFFINITY
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Electronegativity/ Eletron Affinity: a measure of the ability of an atom in a chemical compound to attract electrons. To put that in simpler terms, the energyr eleased whn an electron is added to an atom.
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The electronegativity decreases when going towards the element francium and increases when going towards hydrgoen. The trend then increases to the right of the periodic table, decreasing as it moves the the left towards hydrogen.
