The p-Block Elements

Which of the following is the wrong statement?

• ONCl and ONO^- are not isoelectronic

• O₃ molecule is linear

• Ozone is violet-black in solid state

• Ozone is violet-black in solid state

The molecule having smallest bond angle is

• NCl₃

• AsCl₃

• SbCl₃

• SbCl₃

Which of the following statement is wrong?

• The stability of hydrides increases from NH₃ to BiH₃ in group 15 of the periodic table.

• Nitrogen cannot form dπ-pπ bond.

• Single N - N bond is weaker than the single P - P bond.

• Single N - N bond is weaker than the single P - P bond.

Which one of the following orders presents the correct sequence of the increasing basic nature of the given oxides?

• Al₂O₃ < MgO < Na₂O < K₂O

• MgO < K₂O < Al₂O₃ < Na₂O

• Na₂O < K₂O < MgO < Al₂O₃

• Na₂O < K₂O < MgO < Al₂O₃

Which of the following statements regarding sulphur is incorrect?

• S₂ molecule is paramagnetic. 

• The vapour at 200ºC consists mostly of S₈ rings.

• At 600ºC the gas mainly consists of S₂ molecules. 

• At 600ºC the gas mainly consists of S₂ molecules. 

The structure of IF₇ is

• square pyramid

• trigonal bipyramid

• octahedral

• octahedral

Boron cannot form which one of the following anions?

• BF₆^3-

• BH₄^-

• B(OH)₄^-

• B(OH)₄^-

29.5 mg of an organic compound containing nitrogen was digested according to Kjeldahl’s method and the evolved ammonia was absorbed in 20 mL of 0.1 M HCl solution. The excess of the acid required 15 mL of 0.1 M NaOH solution for complete neutralization. The percentage of nitrogen in the compound is

• 59.0

• 47.4

• 23.7

• 23.7

Which of the following reactions is an example of a redox reaction?

• XeF₄ + O₂F₂ → XeF₆ + O₂

• XeF₂ + PF₅ → [XeF]+PF₆^–

• XeF₆ + H₂O → XeOF₄ + 2HF

• XeF₆ + H₂O → XeOF₄ + 2HF

The products obtained when chlorine gas reacts with cold and dilute aqueous NaOH are

• ClO^– and ClO₃^–

• ClO₂^- and ClO₃^-

• Cl^– and ClO^–

• Cl^– and ClO^–