Actinides exhibit larger number of oxidation state than that of corresponding lanthanides. The reason behind this aspect is

• lesser energy difference between 5f and 6d-orbitals than between 4f and 5d-orbitals

• larger atomic size of actinides than the lanthanides

• more energy difference between 5f and 6d orbitals than between 4f and 5d-orbitals

• greater reactive nature of the actinides than the lanthanides

The correct increasing order of ionic radii of the following Ce³⁺, La³⁺, Pm³⁺ and Yb³⁺ is 

• Yb³⁺ < Pm³⁺< Ce³⁺<La³⁺

• Ce³⁺< Yb³⁺<Pm³⁺<La³⁺

• Yb³⁺< Pm³⁺< La³⁺<Ce³⁺

• Pm³⁺ < La³⁺< Ce³⁺ < Yb³⁺

More the number of oxidation states are exhibited by the actinoids than by the lanthanoids. The main reason for this is:

• more energy difference between 5f and 6d orbitals than that between 4f and 5d orbitals

• the lesser energy difference between 5f and 6d orbitals than that between 4f and 5d orbitals

• the greater metallic character of the lanthanoids than that of the corresponding actinoids

• the greater metallic character of the lanthanoids than that of the corresponding actinoids

Which one of the following ions is the most stable in aqueous solution?

• Cr³⁺

• V³⁺

• Ti³⁺

• Ti³⁺

[CuCl₄]^2- exists while [CuI₄]^2- does not exist, because

• I^- is stronger reductant than Cl^-

• I^- is weaker reductant than Cl^-

• I^- is stronger oxidant than Cl^-

• None of the above

The reason for greater range of oxidation states in actinoids is attributed to

• The radioactive nature of actinoids

• Actinoid contraction

• 5f, 6d and 7s levels having comparable energies

• 5f, 6d and 7s levels having comparable energies

The shape of gaseous SnCl₂ is

• Tetrahedral

• Linear

• Angular

• T-shape

Identify the incorrect statement among the following:

• There is a decrease in the radii of the atoms or ions as one proceeds from La to Lu.

• Lanthanoid contraction is the accumulation of successive shrinkages

• As a result of lanthanoid contraction, the properties of 4d series of the transition elements have no similarities with the 5d series of elements

• As a result of lanthanoid contraction, the properties of 4d series of the transition elements have no similarities with the 5d series of elements

It is because of inability of ns² electrons of the valence shell to participate in bonding that

• Sn²⁺ is reducing while Pb⁴⁺ is oxidising

• Sn²⁺ is oxidising while Pb⁴⁺ is reducing

• Sn²⁺ and Pb²⁺ are both oxidising and reducing

• Sn²⁺ and Pb²⁺ are both oxidising and reducing

Name the gas that can readily decolourises acidified KMnO₄ solution

• CO₂

• SO₂

• NO₂

• NO₂