The Actinoids

Step 1: Understanding the Concept:
Actinoids show variable oxidation states. The maximum +7 oxidation state is exhibited by Np, Pu, and Am.

Step 2: Detailed Explanation:
Neptunium (Np) and Plutonium (Pu) can exhibit +7 oxidation state (e.g., NpO , PuO ).
Th shows only +4, Pa shows +4 and +5, U shows +6 max, Cm shows +3/+4, Bk shows +3/+4, Fm shows +3.

Step 3: Final Answer:
The pair that exhibits maximum oxidation state of +7 is Np and Pu.

Step 1: Understanding the Question:
The question asks for the specific classification or series within the periodic table for the element Americium.
Americium is a synthetic radioactive element with the atomic symbol Am and atomic number 95.

Step 3: Detailed Explanation:
Americium (Am) has an atomic number of 95.
Its electronic configuration can be represented as .
Elements with atomic numbers ranging from 89 (Actinium) or 90 (Thorium) to 103 (Lawrencium) are characterized by the filling of the orbitals.
These elements are collectively known as the Actinide series and are placed in the second row of the f-block at the bottom of the periodic table.
Since Americium (95) falls within this range, it is an actinide.

Step 4: Final Answer:
Americium belongs to the Actinide series, which corresponds to option (C).