Question

Choose the correct order of the following:

• A. $N - H > P - H > As - H > Sb - H$ : Polarity order
• B. $Mg ^{2+}( aq )> Sr ^{2+}( aq )> Ba ^{2+}( aq )$ : Hydrated radius order
• C. $Mg ^{2+}( aq )> Sr ^{2+}( aq )> Ba ^{2+}( aq )$ : Ionic mobility order
• D. $NaF > MgO > SrO$ : Lattice energy order

Answer 1

Answer: (B)

(A) For more polarity electronegativity difference should be more $E.N. (P) \approx E.N. (H) N - H > As - H > Sb - H > P - H$ is the order,
(B) and
(C) more is the size is gaseous phase less is hydration thus less is hydrated size
$\therefore $ more is ionic mobility.
(D) Lattice energy depends on charge of cation and anion and internuclear distance thus order $MgO > SrO > NaF$