Manipal Entrance Test 2015 Chemistry Paper

(a) Metallic radii increase in a group from top to bottom. Thus, Li < Na < K < Rb is true.
(b) Electron gain enthalpy of Cl > F and afterwards it decreases along a group.
(c) Ionisation enthalpy increase along a period left to right but due to presence of half-filled orbital in N, ionisation enthalpy of N > O.
Thus B < C < N < O is incorrect.
(d) For isoelectronic species,
ionic size ∝

1

atomic number

Thus , Al3+<Mg2+<Na+<F− is true.