Maximum number of different oxidation states in its compounds:

The correct answer is option B, Am (Americium). Americium is a chemical element with atomic number 95 and belongs to the actinide series of elements. It is a synthetic element and is not found naturally on Earth.

Explanation:

Oxidation states:
Oxidation state, also known as oxidation number, is a measure of the degree of oxidation of an atom in a chemical compound. It indicates the number of electrons that an atom gains or loses when it forms a compound.

The maximum number of different oxidation states that an element can exhibit depends on its electronic configuration and the availability of different valence orbitals.

Electronic configuration of Americium:
The electronic configuration of Americium can be represented as [Rn] 5f7 7s2. The 5f and 7s orbitals are the valence orbitals that participate in chemical bonding.

Explanation of the correct answer:
Americium (Am) exhibits the maximum number of different oxidation states among the given elements. It can show oxidation states ranging from +2 to +7.

Reason:
The presence of seven 5f electrons in the valence shell of Americium allows for a wide range of oxidation states. These electrons can be either gained or lost to form compounds with different oxidation states.

Some of the common oxidation states of Americium include +2, +3, +4, +5, and +6. In these oxidation states, Americium forms compounds with different ligands, such as halides, oxides, and complex ions.

The ability of Americium to exhibit a wide range of oxidation states is due to the flexibility of its 5f orbitals in accommodating different numbers of electrons. This flexibility arises from the large size and complex electron configuration of the actinide elements.

Conclusion:
In conclusion, Americium (Am) shows the maximum number of different oxidation states among the given elements. Its electronic configuration and the availability of seven 5f electrons in its valence shell allow for a wide range of oxidation states from +2 to +7.