Four successive members of the first row transition elements are listed below with their atomic numbers. Which one of them is expected to have the highest third ionisation enthalpy? 

• Vanadium (Z = 23)

• Manganese (Z = 25)

• Chromium (Z= 24)

• Iron (Z = 26)

Point out in which of the following properties oxygen differs from the rest of the members of its family (Group-VIA)?

• High value of ionisation energies

• Oxidation states (2,4,6)

• Polymorphism

• Formation of hydrides

Which ion is colourless?

• Cr⁴⁺

• Sc³⁺

• Ti³⁺

• V⁴⁺

Which element from group V gives most basic compound with hydrogen?

• Nitrogen

• Bismuth

• Arsenic

• Phosphorus

The oxidation state of oxygen is zero in

• CO

• O₃

• SO₂

• H₂O₂

The d-block elements consists mostly of

• mono-valent metals

• all non-metals

• elements which generally form stoichiometric metal oxide

• many metals with catalytic properties

Which one of the following is an example of non-typical transition elements?

• Li, K, Na

• Be, Al, Pb

• Zn, Cd, Hg

• Ba, Ca, Sr

Which of the following properties increases on going down from F to I in group VII-A of the periodic table?

• Electronegativity

• Volatile nature

• Ionic radius

• Oxidising power

Which of the following statement is not correct?

• La(OH)₃ is less basic than Lu(OH)₃.

• In lanthanide series ionic radius of Lu³⁺ ion decreases.

• La is actually an element of transition series rather lanthanide.

• Atomic radius of Zr and Hf are same because of lanthanide contraction.

E°= -0.44V for the reaction, Fe²⁺ + 2e^- → Fe and E°= -0.76 V for the reaction, Zn²⁺ + 2e^- → Zn. Which of the following statement is correct?

• Fe is more electropositive

• Zn is more electropositive

• Zn is more electronegative

• None of the above