Explanation:
Electronic Configuration for Li: 1s²2s¹
Electronic Configuration for Cl: [Ne]3s²3p⁵
When Lithium and Chlorine bonds together, the electron in the Lithium 2s subshell will be transfered to the Chlorine 3p subshell, giving both the Lithium and Chlorine atoms a complete 1st and 3rd energy levels respectively.
Formula for Lithium chloride: LiCl.