Question

Use the chart to determine which pair of atoms has the greatest difference in electronegativity.

Answer 1

Here, most electronegative element = Fluorine (4)
Least electronegative = Potassium (0.82)

In short, Fluorine(F) & Potassium (K) have greatest difference in electronegativity of about 3.18

Hope this helps!

Answer 2

The answer is: the greatest difference in electronegativity have K and F.

Electronegativity (χ) is a property that describes the tendency of an atom to attract a shared pair of electrons.  

Atoms with higher electronegativity attracts more electrons towards it, electrons are closer to that atom.  

For example fluorine has electronegativity χ = 4 and potassium χ = 0.82, fluorine attracts electron and it has negative charge and sodium has positive charge.  

Δχ(K-F) = 4 - 0.82.

Δχ(K-F) = 3.18; electronegativity difference between potassium and fluorine.

When the electronegativity difference is greater, the bond polarity is increasing.