The trends for electronegativity is that the value increases across the periods (rows) of the periodic table. Lithium 1.0 and Fluorine 4.0 in period 2
The electronegativity also increases up a group (column) of the periodic table. Lithium 1.0 and Francium 0.7 in Group I.
Therefore Francium (Fr) in the lower left Group I Period 7 has the lowest electronegativity value at 0.7 and Fluorine (F) upper right Group 17 Period 2 has the highest electronegativity value at 4.0.
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