Based on the compounds of group 15 elements, the correct statement(s) is (are)
(A) > (Acidic)
Acidic strength a oxidation state a Non Metallic character.
Bi2O5 is more basic
(B) NF3 is more covalent BiF3
(C) Boiling point of NH3 > PH3 (H–bond in NH3)
(D) P – P single is stronger than N – N single bond due to lone pair – lone pair repulsion
Let's analyze each statement one by one based on the properties of Group 15 elements (N, P, As, Sb, Bi).
This is correct. NH3 has a higher boiling point than PH3 due to strong hydrogen bonding in NH3. In PH3, hydrogen bonding is absent because phosphorus is less electronegative. Boiling points: NH3 (-33°C) and PH3 (-87°C).
This is correct. On moving down the group, the metallic character increases, so oxides become more basic. N2O5 is acidic, while Bi2O5 is amphoteric but with more basic character compared to N2O5.
This is incorrect. The N-N single bond (bond enthalpy ~163 kJ/mol) is weaker than the P-P single bond (~200 kJ/mol) due to smaller size of nitrogen leading to greater lone pair-lone pair repulsion.
This is correct. Covalent character decreases down the group for halides due to increase in size and decrease in polarizing power. NF3 is covalent, while BiF3 is ionic.
Correct statements are 1, 2, and 4.
Hydrogen Bonding: Occurs when H is bonded to highly electronegative atoms (N, O, F), leading to higher boiling points.
Acidic-Basic Nature of Oxides: Across a period, acidity increases; down a group, basicity increases.
Bond Strength: Affected by atomic size and lone pair repulsion. Smaller atoms may have weaker bonds due to repulsion.
Fajans' Rules: Smaller cation size and higher charge increase covalent character. NF3 has smaller N3+ compared to Bi3+ in BiF3, so more covalent.