IMO Practice Test — The p-Block Elements

The total number of P–H bonds in H₃PO₂, H₃PO₃ and H₃PO₄ taken together is:

Which one of these is NOT a correct reason for choosing ~700 K (not a lower temperature) in the Haber process?

Among NH₃, PH₃, AsH₃ and SbH₃, the hydride with the highest bond angle is:

The number of lone pairs of electrons on the central atom in BrF₅ is:

Hot concentrated H₂SO₄ reacts with copper to liberate:

Among the halogens, the one with the most negative (most exothermic) electron-gain enthalpy is:

The shape of XeO₃ is:

Which reaction correctly represents partial hydrolysis of XeF₆?

Assertion: the +5 oxidation state becomes less stable down Group 15. Reason: the inert-pair effect makes the ns² electrons increasingly reluctant to bond. Choose the correct option.

The interhalogen with a pentagonal bipyramidal shape is:

Which property explains why F₂ is a stronger oxidising agent than Cl₂ despite a less negative electron-gain enthalpy?

On dissolving SO₃ in concentrated H₂SO₄ during the Contact process, the product formed is:

The brown gas evolved when copper reacts with concentrated nitric acid is:

The number of Xe–F bonds and lone pairs respectively in XeF₄ is: