In which of the following options order of arrangement does not agree with the variation of property indicated against it?

In which of the following options order of arrangement does not agree

1.	In which of the following options order of arrangement does not agree with the variation of property indicated against it?
Answer» `Al^(3+) lt Mg^(2+) lt NA^(+) lt F^(-)` -(INCREASING IONIC size) `B lt C lt N lt O` (increasing FIRST ionisation enthalpy) `I lt Br lt CI lt F`(increasing electron gain enthalpy) `Li lt Nalt K lt RB` (increasing metallic radius) Solution :As Nitrogen is having greater stability due to its halfed filled ELECTRONIC configuration, then its ionisation enthalpy is higher than that of oxygen. Thus, option (B) is incorrect. Due to the negative electron gain enthalpy of flourine is lower than of chlorine because of the electron-electron repulsion in the small size of flourine.