1.The incorrect order is:a.He<Ne<Ar<Kr<Xe\text{He} < \text{Ne} < \text{Ar} < \text{Kr} < \text{Xe}He<Ne<Ar<Kr<Xe (atomic radius)b.He>Ne>Ar>Kr>Xe\text{He} > \text{Ne} > \text{Ar} > \text{Kr} > \text{Xe}He>Ne>Ar>Kr>Xe (ionisation enthalpy)c.He<Ne<Ar<Kr<Xe\text{He} < \text{Ne} < \text{Ar} < \text{Kr} < \text{Xe}He<Ne<Ar<Kr<Xe (density)d.He<Ne<Ar<Kr<Xe\text{He} < \text{Ne} < \text{Ar} < \text{Kr} < \text{Xe}He<Ne<Ar<Kr<Xe (electron gain enthalpy)Login to continueOnly logged in users canattempt or see the solution.
