Which of the following has least tendency to undergo catenation ?

Options

A. `C`
B. `Si`
C. `Ge`
D. Sn`

Explanation

To determine which element has the least tendency to undergo catenation among the given options (C, Si, Ge, Sn), we can follow these steps:

### Step-by-Step Solution:

1. **Understand Catenation**:
- Catenation is the ability of an element to form chains or rings by bonding with itself. This property is most commonly associated with carbon, which can form long chains due to its ability to create strong covalent bonds with other carbon atoms.

2. **Identify the Elements**:
- The elements in question are Carbon (C), Silicon (Si), Germanium (Ge), and Tin (Sn). All these elements belong to Group 14 of the periodic table.

3. **Analyze Trends in Catenation**:
- As we move down the group from Carbon to Tin, the atomic size increases. Larger atoms tend to form weaker bonds due to increased distance between the nuclei of bonded atoms. This results in a decreased ability to catenate.

4. **Compare the Elements**:
- Carbon (C) has the strongest catenation ability due to its small size and strong covalent bonds.
- Silicon (Si) can also catenate, but to a lesser extent than carbon.
- Germanium (Ge) has a further reduced ability to catenate compared to silicon.
- Tin (Sn), being the largest atom among these, has the weakest ability to catenate due to its larger size and weaker bonds.

5. **Conclusion**:
- Therefore, among the given options, Tin (Sn) has the least tendency to undergo catenation.

### Final Answer:
The element with the least tendency to undergo catenation is **Tin (Sn)**.

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