Which of the following statement is/are true ?

Options

A. It is impossible to satisfy the octet rule for all atoms in `XeF_2`
B. `MgSO_4` is soluble in water because hydration energy of `MgSO_4` is higher in comparision to its lattice energy
C. The bond in `NO^(+)` should be stronger than the bond in `NO^-`
D. For ozone molecule, one oxygen-oxygen bond is stonger than the other oxygen-oxygen bond.

Explanation

To determine which of the statements are true, we will analyze each statement step by step.

### Step 1: Analyze the first statement
**Statement:** It is impossible to satisfy the octet rule for all atoms in XCF2.

- **Analysis:**
- XCF2 refers to a compound where X is a noble gas, specifically xenon (Xe).
- Noble gases have a complete octet and are stable in their elemental form.
- When xenon forms a compound like XeF2, it can exceed the octet rule because it can accommodate more than 8 electrons due to the presence of d-orbitals.
- Therefore, it is true that it is impossible to satisfy the octet rule for all atoms in XeF2, as xenon can have more than 8 electrons in its valence shell.

**Conclusion:** This statement is **true**.

### Step 2: Analyze the second statement
**Statement:** MgSO4 is soluble in water because hydration energy of MgSO4 is higher in comparison to its lattice energy.

- **Analysis:**
- Hydration energy is the energy released when ions are solvated in water.
- Lattice energy is the energy required to separate the ions in a solid ionic compound.
- For a compound to be soluble, the hydration energy must be greater than the lattice energy.
- MgSO4 is known to be soluble in water, which supports that its hydration energy is indeed higher than its lattice energy.

**Conclusion:** This statement is **true**.

### Step 3: Analyze the third statement
**Statement:** The bond in NO+ should be stronger than the bond in NO-.

- **Analysis:**
- To analyze this, we need to look at the bond order of both NO+ and NO-.
- NO has 15 electrons, NO+ has 14 electrons (removing one electron from the antibonding orbital), and NO- has 16 electrons (adding one electron to the antibonding orbital).
- The bond order for NO+ is calculated as (10 bonding electrons - 4 antibonding electrons) / 2 = 3.
- The bond order for NO- is (10 bonding electrons - 6 antibonding electrons) / 2 = 2.
- Since bond order is directly related to bond strength, a higher bond order indicates a stronger bond. Thus, NO+ has a stronger bond than NO-.

**Conclusion:** This statement is **true**.

### Step 4: Analyze the fourth statement
**Statement:** For the ozone molecule, one oxygen-oxygen bond is stronger than the other oxygen-oxygen bond.

- **Analysis:**
- Ozone (O3) has resonance structures where the bonds between the oxygen atoms have partial double bond character.
- Due to resonance, both O-O bonds in ozone are equivalent and have the same bond strength and length.
- Therefore, it is incorrect to say that one bond is stronger than the other.

**Conclusion:** This statement is **false**.

### Final Conclusion
The true statements are:
1. It is impossible to satisfy the octet rule for all atoms in XCF2. (True)
2. MgSO4 is soluble in water because hydration energy of MgSO4 is higher in comparison to its lattice energy. (True)
3. The bond in NO+ should be stronger than the bond in NO-. (True)
4. For the ozone molecule, one oxygen-oxygen bond is stronger than the other oxygen-oxygen bond. (False)

Thus, the correct answer is that statements 1, 2, and 3 are true.