Which of the following oxidation state si common for all lanthanoids?

Options

A. `+2`
B. `+3`
C. `+4`
D. `+5`

Answer

To determine the common oxidation state for all lanthanoids, we can follow these steps:

### Step 1: Understand the Lanthanoids
Lanthanoids are a series of 15 chemical elements in the periodic table from lanthanum (La) to lutetium (Lu). They are known for their similar properties and electronic configurations.

### Step 2: Analyze the Oxidation States
Lanthanoids exhibit variable oxidation states. The common oxidation states include +2, +3, +4, and +5. However, we need to identify which of these is common to all lanthanoids.

### Step 3: Identify the Electronic Configuration
The outer shell electronic configuration of lanthanides primarily involves the 4f and 5d orbitals. The presence of these orbitals allows for different oxidation states, but the energy gap between them limits the number of oxidation states.

### Step 4: Determine the Common Oxidation State
Among the oxidation states mentioned, the +3 oxidation state is the most prevalent and is exhibited by all lanthanoids. This is due to the stability associated with the loss of three electrons from the 6s and 4f orbitals.

### Conclusion
Therefore, the common oxidation state for all lanthanoids is +3.

### Final Answer
The correct option is +3.

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