Fructose

EN and Oxidation Number (O.N.)
Delta EN vs Bond Type
For example in NaCl (Sodium Chloride or table salt), Cl is more electronegative (EN = 3.0) than Na
(EN = 0.9). Therefore, according to the rules above, we assign both (2) shared electrons to Cl and
0 shared electrons to Na.
Cl has 7 valence electrons and 6 unshared electrons in its outer shell. Na has 1 valence electron
and 0 unshared electrons in its outer shell.
Using the equation above for Cl: O.N. = 7-(2+6) = 7-8 = -1. Using the equation above for Na: O.N.
= 1-(0-0) = 1-0 = +1.
Delta EN and Bond Type
When you look at a bond between any two elements X and Y and ask "Is the X-Y bond ionic or
covalent?", the answer in almost every case is "Partly Ionic and Partly Covalent".
The partial-ionic/partial-covalent character of any given bond X-Y is directly related to the
Electronegativity Difference (Delta EN), which is the arithmetic difference between the EN values
of X and Y.
The relationship between Delta EN and Bond Type is shown in the picture below.
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