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. `sp^3d^2` hybrid orbitals are directed towards the corners of a regular octahedron
D. `dsp^3` hybrid orbitals have trigonal bipyramidal shape

Answer

To determine which statement is not correct regarding hybridization and molecular orbitals, let's analyze each statement step by step.

### Step 1: Understanding Hybridization
Hybridization is a concept in chemistry that describes the mixing of atomic orbitals to form new hybrid orbitals. These hybrid orbitals are then used to form bonds in molecules.

### Step 2: Evaluating the First Statement
The first statement claims: "Hybridization is mixing of atomic orbitals prior to their combination into molecular orbitals."

- This statement implies that hybridization occurs before the formation of molecular orbitals. However, hybridization actually refers to the process of mixing atomic orbitals to create hybrid orbitals, which then participate in bond formation. The mixing occurs to create orbitals that can form molecular orbitals, but this is not the same as saying hybridization happens before the formation of molecular orbitals. Therefore, this statement is **incorrect**.

### Step 3: Evaluating the Second Statement
The second statement claims: "sp² hybrid orbitals are formed from two p orbitals and one s orbital."

- This statement is correct. In sp² hybridization, one s orbital mixes with two p orbitals to form three equivalent sp² hybrid orbitals, which are arranged in a trigonal planar geometry.

### Step 4: Evaluating the Third Statement
The third statement claims: "sp³d² hybrid orbitals are directed towards the corners of the regular octahedron."

- This statement is also correct. In sp³d² hybridization, the hybrid orbitals are arranged in an octahedral geometry, with the hybrid orbitals pointing towards the corners of an octahedron.

### Step 5: Evaluating the Fourth Statement
The fourth statement claims: "dsp³ hybrid orbitals have a triangular bipyramidal shape."

- This statement is correct as well. In dsp³ hybridization, the arrangement of the hybrid orbitals results in a triangular bipyramidal shape.

### Conclusion
After evaluating all the statements, we find that the first statement is the only incorrect one. Therefore, the answer to the question is that the first statement is not correct.

### Final Answer
The statement that is not correct is: "Hybridization is mixing of atomic orbitals prior to their combination into molecular orbitals."

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