231.

Ionisation potential values of noble gases decrease down the group with increase in atomic size. Xenon forms binary fluorides by the direct reaction of elements. Identify the correct statement(s) from below.

• Only the heavier noble gases form such compounds

• It happens because the noble gases have higher ionisation energies

• It happens because the compounds are formed with electronegative ligands

• Octet of electrons provide the stable arrangements 

If Cl₂ is passed through hot aqueous NaOH, the products formed have Cl in different oxidation states. These are indicated as

• -1 and +1

• -1and +5

• +1 and +5

• -1and +3

The hydrides of the first elements in groups 15-17, namely NH₃, H₂O and HF respectively show abnormally high values for melting and boiling points. This is due to

• small size of N, O and F

• the ability to form extensive intermolecular H-bonding

• the ability to form extensive intramolecular H-bonding

• effective van der Waals' interaction

Among the following observations, the correct one that differentiates between ${\mathrm{SO}}_3^{2-}$ and ${\mathrm{SO}}_4^{2-}$ is

• both form precipitate with BaCl₂,${\mathrm{SO}}_3^{2-}$ dissolves in HCl but ${\mathrm{SO}}_4^{2-}$ does not.

• ${\mathrm{SO}}_3^{2-}$ forms precipitate with BaCl₂,${\mathrm{SO}}_4^{2-}$ does not.

• ${\mathrm{SO}}_4^{2-}$  forms precipitate with BaCl_2, ${\mathrm{SO}}_3^{2-}$does not

• both form precipitate with BaCl_2, ${\mathrm{SO}}_4^{2-}$ dissolves in HCl but ${\mathrm{SO}}_3^{2-}$ does not.

'Sulphan' is

• a mixture of SO₃ and H₂SO₅

• 100% conc. H₂SO₄

• a mixture of gypsum and conc. H₂SO₄

• 100% oleum (a mixture of 100% SO₃ in 100% H₂SO₄)

On heating, chloric acid decomposes to

• HClO₄, Cl₂, O₂ and H₂O

• HClO₂, Cl₂, O₂ and H₂O

• HClO, Cl₂O and H₂O₂

• HCl, HClO, Cl₂O and H₂O

The number of acidic protons in H₃PO₃ are

• 0

• 1

• 2

• 3

Which one of the following is not true at room temperature and pressure?

• P₄O₁₀ is white solid

• SO₂ is a colourless gas

• SO₃ is a colourless gas

• NO₂ is a brown gas

An element belongs to group 15 and third period of the Periodic Table. Its electronic configuration wil be

• 1s²2s²2p³

• 1s²2s²2p⁴

• 1s²2s²2p⁶3s²3p³

• 1s²2s²2p⁶3s²3p²

In the brown ring complex [Fe(H₂O)₅(NO)]SO₄, nitric oxide behaves as

• NO⁺

• neutral NO molecule

• NO^-

• NO^2-