Which is the strongest base among the following ?

Options

A. `La(OH)_(3)`
B. `Lu (OH)_(3)`
C. `Ce(OH)_(3)`
D. `Yb(OH)_(3)`

Answer

To determine which is the strongest base among the given lanthanide oxides (La2O3, CeO2, Yb2O3, and Lu2O3), we can follow these steps:

### Step 1: Identify the Elements
The elements in question are:
- La (Lanthanum) with atomic number 57
- Ce (Cerium) with atomic number 58
- Yb (Ytterbium) with atomic number 70
- Lu (Lutetium) with atomic number 71

### Step 2: Understand Basicity of Oxides
The basicity of metal oxides generally decreases as you move from left to right across the periodic table. In the case of lanthanides, the basic character of their oxides can be influenced by their oxidation states and the stability of the oxide formed.

### Step 3: Analyze the Oxides
- La2O3 (Lanthanum oxide) tends to be more basic.
- CeO2 (Cerium oxide) is amphoteric, meaning it can act as both an acid and a base.
- Yb2O3 (Ytterbium oxide) is less basic than La2O3.
- Lu2O3 (Lutetium oxide) is also less basic compared to La2O3.

### Step 4: Compare Basic Strengths
Based on the general trend of basicity in lanthanide oxides:
- La2O3 > Yb2O3 > Lu2O3 > CeO2

### Conclusion
Thus, the strongest base among the given lanthanide oxides is **La2O3 (Lanthanum oxide)**.

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