The electronic configuration of a chloride ion in a compound of BeCl2 is
2.8.8
This is because chlorine atom which electronic configuration 2.8.7 gain one electron form Be to form chloride ion with 2.8.8 electronic configuration. BeCl2 is an ionic bond which is formed by a metal and a non metal.metal (Be)loses electron and become positively charged while non metal (Cl2) gain electron and become negative charged.
