The chemistry of the actinoid elements is not so smooth as that of the lanthanoid. Justify this statement by giving some example from the oxidation state of these elements

Explanation

To justify the statement that the chemistry of the actinoid elements is not as smooth as that of the lanthanoid elements, we can analyze the oxidation states of both groups of elements.

### Step-by-Step Solution:

1. **Understanding Lanthanoids**:
- The lanthanoid series consists of 15 elements from lanthanum (La, atomic number 57) to lutetium (Lu, atomic number 71).
- The most common oxidation state for lanthanoids is +3. This is due to the relatively stable electronic configuration where the 4f electrons are being filled.

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