Which one of them is the weakest ?

Options

A. lonic bond
B. Covalent bond
C. Metallic bond
D. van der Wall's forces

Explanation

To determine which type of bond or interaction is the weakest among the various types of chemical bonds, we can analyze the different types of bonds and their relative strengths.

### Step-by-Step Solution:

1. **Identify the Types of Bonds**:
- The main types of bonds and interactions we need to consider are:
- Ionic Bonds
- Covalent Bonds
- Metallic Bonds
- Van der Waals Forces (including dipole-dipole interactions and hydrogen bonding)

2. **Understand Ionic Bonds**:
- Ionic bonds are formed through the transfer of electrons from one atom to another, resulting in the formation of positively and negatively charged ions. The electrostatic force of attraction between these oppositely charged ions is very strong, making ionic bonds one of the strongest types of chemical bonds.

3. **Understand Covalent Bonds**:
- Covalent bonds involve the sharing of electrons between atoms. The strength of covalent bonds can vary, but they are generally strong due to the overlap of atomic orbitals. For example, in methane (CH4), the bonds between carbon and hydrogen are covalent.

4. **Understand Metallic Bonds**:
- Metallic bonds occur between metal atoms, where electrons are delocalized in a 'sea of electrons' around positively charged metal ions. This type of bonding also results in strong attractions, contributing to the properties of metals.

5. **Understand Van der Waals Forces**:
- Van der Waals forces are much weaker than the previously mentioned bonds. They include:
- Dipole-dipole interactions: Occur between polar molecules.
- Hydrogen bonding: A special case of dipole-dipole interactions that occurs when hydrogen is bonded to highly electronegative atoms like oxygen, nitrogen, or fluorine.
- London dispersion forces: Weak attractions that occur due to temporary dipoles in nonpolar molecules.

6. **Compare the Strengths**:
- Among the bonds and interactions discussed:
- Ionic Bonds > Covalent Bonds > Metallic Bonds > Van der Waals Forces
- Van der Waals forces are the weakest due to their nature as temporary and weak electrostatic attractions.

7. **Conclusion**:
- Therefore, the weakest type of bond or interaction among those listed is the **Van der Waals force of attraction**.

### Final Answer:
The weakest bond is the **Van der Waals force of attraction**.