p block

Which of the following elements can be involved in pπ–dπ bonding?

• Carbon

• Nitrogen

• Boran

• Phosphorous

Which of the following pairs of ions are isoelectronic and isostructural?

• CO₃^2–, NO₃^–

• ClO₃^– , CO₃^2–

• SO₃^2–, NO₃^–

• ClO₃^– , SO₃^2–

Bond dissociation enthalpy of E—H (E = element) bonds is given below. Which of the compounds will act as strongest reducing agent?

Compound NH₃ PH₃ AsH₃ SbH₃

Δdiss (E—H)/kJ mol^–1 389 322 297 255

• NH₃

• PH₃

• AsH₃

• SbH₃

Which of the following acids forms three series of salts?

• H₃PO₂

• H₃BO₃

• H₃PO₄

• H₃PO₃

Strong reducing behaviour of H₃PO₂ is due to

• Low oxidation state of phosphorus

• Presence of two –OH groups and one P–H bond

• Presence of one –OH group and two P–H bonds

• High electron gain enthalpy of phosphorus

On heating lead nitrate forms oxides of nitrogen and lead. The oxides formed are ______.

• N₂O, PbO

• NO₂, PbO

• NO, PbO

• NO, PbO₂

Which of the following elements does not show allotropy?

• Nitrogen

• Bismuth

• Antimony

• Arsenic

Maximum covalency of nitrogen is ______________.

• 3

• 4

• 5

• 6

Which of the following statements is wrong?

• Single N–N bond is stronger than the single P–P bond.

• PH₃ can act as a ligand in the formation of coordination compound with transition elements.

• NO₂ is paramagnetic in nature.

• Covalency of nitrogen in N₂O₅ is four

A brown ring is formed in the ring test for NO₃^– ion. It is due to the formation of

• [Fe(H₂O)₅ (NO)]²⁺

• FeSO₄.NO₂

• [Fe(H₂O)₄(NO)₂]²⁺

• FeSO₄.HNO₃