Select the incorrect statement.

Options

A. Double bond is shorter than a single bond
B. `sigma-`bond is weaker than a `pi-` bond
C. Double bond is stronger than a single bond
D. Covalent bond is stronger than a hydrogen bond

Explanation

To solve the question of selecting the incorrect statement, we will analyze each statement provided.

### Step-by-Step Solution:

1. **Statement 1:** "Double bond is shorter than a single bond."
- **Analysis:** This statement is correct. A double bond involves more electron sharing between two atoms compared to a single bond, which results in a shorter bond length due to increased attraction between the nuclei and the shared electrons.

2. **Statement 2:** "Sigma bond is weaker than pi bond."
- **Analysis:** This statement is incorrect. Sigma bonds are formed by the head-on overlap of atomic orbitals and are generally stronger than pi bonds, which are formed by the sidewise overlap of p orbitals. Therefore, this statement is the incorrect one.

3. **Statement 3:** "Double bond is stronger than a single bond."
- **Analysis:** This statement is correct. A double bond consists of one sigma bond and one pi bond, making it stronger than a single bond, which consists of only one sigma bond. The bond dissociation energy for double bonds is higher than for single bonds.

4. **Statement 4:** "Covalent bond is stronger than the hydrogen bond."
- **Analysis:** This statement is correct. Covalent bonds involve the sharing of electrons between atoms within a molecule, making them generally stronger than hydrogen bonds, which are intermolecular attractions.

### Conclusion:
After analyzing all statements, we find that **Statement 2** is the incorrect one: "Sigma bond is weaker than pi bond."

### Final Answer:
The incorrect statement is: **"Sigma bond is weaker than pi bond."**

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