0.97-2.83 = -1.86 (Pauling scale) ref.: http://www.webelements.com/periodicity/electroneg_allred_rochow/

The of a bond between two is calculated taking the difference between the electronegativities (tendency to attract/accept electrons) of the two elements.

You can think of it like a magnetic attraction. Similar signs will repel each other (no bond), and dissimilar signs will attract in proportion to the difference, with the more electronegative element acquiring a negative charge, and the other a positive charge.

The electronegativities of Li and Cl are 0.97 and 2.83 respectively. The difference is thus 0.97-2.83, -1.86, indicating an ionic bond with the negative charge on the Cl atom.

0.97-2.83 = -1.86 (Pauling scale) ref.: http://www.webelements.com/periodicity/electroneg_allred_rochow/

The of a bond between two is calculated taking the difference between the electronegativities (tendency to attract/accept electrons) of the two elements.

You can think of it like a magnetic attraction. Similar signs will repel each other (no bond), and dissimilar signs will attract in proportion to the difference, with the more electronegative element acquiring a negative charge, and the other a positive charge.

The electronegativities of Li and Cl are 0.97 and 2.83 respectively. The difference is thus 0.97-2.83, -1.86, indicating an ionic bond with the negative charge on the Cl atom.