Aarti Gupta
Last Activity: 9 Years ago
Element X atomic number 17 is chlorine having electronic configuration 2,8,7(belongs to group 17).Thus it needs only one e- to complete its octet.Now another element Y atomic number 20.Thus configuration will be 2,8,8,2(group 2 element).It gives its two electrons to two chlorine atoms and acquire noble gas configuration and forms Ca2+ ion while Chlorine becomes 2Cl-.The electron dot structure for this divalent halide will be as follows--