Which of the following statement is not correct

Options

A. Hybridization is the mixing of atomic orbitals prior to their combining into molecular orbitals
B. `sp^2` hybrid orbitals are formed from two p atomic orbitals and one s atomic orbital
C. `d^2 sp^3` hybrid orbitals are directed towards the corners of a regular octahedron
D. `dsp^3` hybrid orbitals are all at `90^@` to one another

Explanation

To determine which statement is not correct regarding hybridization and molecular geometry, we will analyze each statement one by one.

### Step 1: Analyze Statement 1
**Statement:** Hybridization is the mixing of atomic orbitals prior to their combining into molecular orbitals.

**Analysis:** This statement is correct. Hybridization involves the combination of atomic orbitals (such as s and p orbitals) to form new hybrid orbitals that can then combine to form molecular orbitals.

### Step 2: Analyze Statement 2
**Statement:** sp² hybrid orbitals are formed from two p orbitals and one s atomic orbital.

**Analysis:** This statement is also correct. In sp² hybridization, one s orbital and two p orbitals mix to form three equivalent sp² hybrid orbitals.

### Step 3: Analyze Statement 3
**Statement:** sp² hybrid orbitals are directed towards the corners of a regular octahedron.

**Analysis:** This statement is incorrect. sp² hybrid orbitals are actually directed towards the corners of a trigonal planar geometry, not an octahedron. An octahedron has sp³d² hybridization.

### Step 4: Analyze Statement 4
**Statement:** d²sp³ hybrid orbitals are directed towards the corners of a regular octahedron.

**Analysis:** This statement is correct. d²sp³ hybridization results in an octahedral geometry where the orbitals are directed towards the corners of an octahedron.

### Step 5: Analyze Statement 5
**Statement:** dsp³ hybrid orbitals are all at 90 degrees to one another.

**Analysis:** This statement is incorrect. While some bonds in a dsp³ hybridization are at 90 degrees (the axial bonds), the equatorial bonds are at 120 degrees. Therefore, this statement is misleading because it does not account for the geometry of the hybridization.

### Conclusion
The statements that are not correct are Statement 3 and Statement 5. However, since the question asks for one statement that is not correct, we can conclude that **Statement 3** is the most directly incorrect regarding sp² hybridization.

### Final Answer
**The statement that is not correct is:** "sp² hybrid orbitals are directed towards the corners of a regular octahedron."

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