Which of the following is correct regarding BeO?

Options

A. BeO is essentially covalent in nature
B. BeO has high value of enthalpy of formation
C. BeO is thermally very stable
D. All the above are correct

Answer

To determine which statement is correct regarding Beryllium Oxide (BeO), let's analyze each option step by step.

### Step 1: Analyze the nature of BeO
- **Statement 1**: "BeO is essentially covalent in nature."
- Beryllium oxide (BeO) is known to exhibit covalent characteristics due to the small size and high charge density of the beryllium ion (Be²⁺). This leads to significant polarization of the oxide ion (O²⁻), resulting in covalent bonding. Therefore, this statement is **correct**.

### Step 2: Examine the enthalpy of formation
- **Statement 2**: "The enthalpy of beryllium oxide is high."
- The formation of BeO from its elements (beryllium and oxygen) involves a significant amount of energy, indicating that BeO is a stable compound. High enthalpy of formation suggests that it is energetically favorable and stable. Thus, this statement is also **correct**.

### Step 3: Assess thermal stability
- **Statement 3**: "BeO is thermally very stable."
- Beryllium oxide is known for its thermal stability. It does not decompose easily upon heating, which indicates that it can withstand high temperatures without breaking down. This statement is therefore **correct**.

### Step 4: Evaluate the overall correctness
- **Statement 4**: "All of these are correct."
- Since all the previous statements (1, 2, and 3) regarding BeO are correct, this statement is also **correct**.

### Conclusion
The correct answer is that all of the statements regarding BeO are correct.

### Summary of Steps:
1. Analyze the covalent nature of BeO.
2. Examine the enthalpy of formation of BeO.
3. Assess the thermal stability of BeO.
4. Conclude that all statements are correct.