d and f BLOCK ELEMENTS

Which actinoid is mentioned as having a maximum oxidation state of +7?

• Plutonium (Pu)
• Uranium (U)
• Protactinium (Pa)
• Neptunium (Np)

Compared to lanthanoids, what is a distinguishing feature of actinoid oxidation states?

• Actinoids only show +3
• Actinoids show fewer oxidation states
• Lanthanoids have a greater range of oxidation states
• Actinoids have a greater range of oxidation states

Which subshell is formally filled last in the actinoid series?

• 6d
• 7s
• 4f
• 5f

What is a common property of both +3 and +4 actinoid ions?

• They are highly stable in water
• They are colorless
• They do not form complexes
• They tend to hydrolyse

How does the actinoid contraction affect the atomic/ionic radii across the series?

• It causes a gradual increase
• It causes random fluctuations
• It causes a gradual decrease
• It has no effect