Lanthanoid compounds in general are less/more basic than actinoid compounds.

Explanation

To determine whether lanthanoid compounds are less or more basic than actinoid compounds, we need to analyze the electronic configurations and the resulting basicity of these compounds.

### Step-by-Step Solution:

1. **Understanding the Elements**:
- Lanthanoids (or lanthanides) consist of the 14 elements from cerium (Ce) to lutetium (Lu) with atomic numbers 58 to 71. They fill the 4f orbitals.
- Actinoids (or actinides) consist of the 14 elements from thorium (Th) to lawrencium (Lr) with atomic numbers 90 to 103. They fill the 5f orbitals.

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