JAMB Chemistry 2010 Paper

Concept:Noble gases are stable because of their complete outermost electron shells.Explanation:Atoms are most stable when their outermost shell is completely filled.For helium, this means a duplet configuration: $1s^2$.For the other noble gases, this means an octet configuration: $ns^2 np^6$.These duplet or octet electron configurations give noble gases no tendency to gain, lose, or share electrons.Therefore, the stability of noble gases is due to having duplet or octet electron configurations, not merely their group number or physical properties.Answer:B. have duplet or octet electron configurations.