d and f BLOCK ELEMENTS

What is the primary reason for the stability of the Mn²⁺ ion?

• Its small ionic radius.
• Its 3d⁵ configuration represents a half-filled d subshell.
• Its high ionization energy.
• Its noble gas core configuration.

What is the effect of increasing pH on a solution of Potassium Dichromate (K₂Cr₂O₇)?

• It converts chromate ions (CrO₄²⁻) to dichromate ions (Cr₂O₇²⁻).
• It precipitates chromium metal.
• It converts dichromate ions (Cr₂O₇²⁻) to chromate ions (CrO₄²⁻).
• It has no effect on the solution.

What is the usual stable oxidation state of an element with a ground state 3d³ configuration?

• +2
• +3
• +4
• +5

What is the usual stable oxidation state of an element with a ground state 3d⁸ configuration?

• +1
• +2
• +3
• +4

How does the variability in oxidation states of transition metals differ from that of non-transition metals?

• Non-transition metals show more oxidation states.
• Transition metals show a wide range of oxidation states, while non-transition metals usually show fewer.
• There is no difference.
• Transition metals show only positive oxidation states.