Least basic among the following is

Options

A. InOH
B. TlOH
C. `B(OH)_3`
D. `Al(OH)_3`

Answer

To determine which compound is the least basic among the given options (ENOH, TLOH, BOH₃, and ALOH₃), we can analyze the basicity of each compound step by step.

### Step 1: Identify the Compounds
The compounds provided are:
1. ENOH (Ethylamine)
2. TLOH (Thallium hydroxide)
3. BOH₃ (Boric acid)
4. ALOH₃ (Aluminum hydroxide)

### Step 2: Understand Basicity
Basicity refers to the ability of a compound to accept protons (H⁺ ions). The more readily a compound can accept protons, the more basic it is.

### Step 3: Analyze Each Compound
1. **ENOH (Ethylamine)**: This is a strong base due to the presence of the amine group (-NH₂), which can easily accept protons.

2. **TLOH (Thallium hydroxide)**: Thallium hydroxide is a strong base as well, as it can dissociate in water to release hydroxide ions (OH⁻).

3. **BOH₃ (Boric acid)**: Boric acid is not a strong base; it is a weak acid. It does not release OH⁻ ions directly but rather accepts hydroxide ions from water, making it less basic.

4. **ALOH₃ (Aluminum hydroxide)**: Aluminum hydroxide is amphoteric, meaning it can act as both an acid and a base. However, it is generally less basic compared to strong bases like TLOH and ENOH.

### Step 4: Compare Basicity
- ENOH and TLOH are strong bases.
- ALOH₃ is amphoteric and less basic than ENOH and TLOH.
- BOH₃ is a weak acid and is therefore the least basic among the options.

### Conclusion
Based on the analysis, the least basic compound among the given options is **BOH₃ (Boric acid)**.

### Final Answer
The least basic among the following is **BOH₃ (Boric acid)**.

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