How many S-S bonds, S-O-S bonds, `sigma`-bonds, `pi`-bonds are present in trimer of sulphur trioxide ?

Options

A. 0,3,16,2
B. 0,3,12,6
C. 0,6,12,16
D. 0,4,12,6

Answer

To determine the number of S-S bonds, S-O-S bonds, sigma bonds, and pi bonds in the trimer of sulfur trioxide (SO₃), we will analyze the structure of the molecule step-by-step.

### Step 1: Understand the structure of sulfur trioxide (SO₃)
Sulfur trioxide consists of one sulfur atom bonded to three oxygen atoms. The molecular structure can be represented as follows:

```
O
||
O = S = O
||
O
```

In the trimer of sulfur trioxide, three SO₃ molecules combine. This means we will have three sulfur atoms and nine oxygen atoms in total.

### Step 2: Identify S-S bonds
In the trimer of sulfur trioxide, there are no direct S-S bonds between the sulfur atoms. Each sulfur atom is bonded to oxygen atoms only.

**S-S bonds = 0**

### Step 3: Identify S-O-S bonds
Each sulfur atom in the trimer is connected to two oxygen atoms, and there are three sulfur atoms. The S-O-S bonds occur at the junctions where the sulfur atoms are connected through oxygen atoms.

For three sulfur atoms, we can visualize the connections:
- Sulfur 1 connects to Oxygen 1 and Oxygen 2
- Sulfur 2 connects to Oxygen 2 and Oxygen 3
- Sulfur 3 connects to Oxygen 3 and Oxygen 1

Thus, there are three S-O-S bonds formed in the trimer.

**S-O-S bonds = 3**

### Step 4: Count sigma bonds
In the SO₃ molecule, each sulfur-oxygen bond is a sigma bond. Each sulfur atom forms three sigma bonds with the three oxygen atoms.

For three sulfur atoms:
- Each sulfur forms 3 sigma bonds, so for 3 sulfur atoms:
3 (sulfur atoms) × 3 (sigma bonds per sulfur) = 9 sigma bonds.

Additionally, there are S-O-S bonds which also contribute to sigma bonds. Each S-O-S bond contributes one sigma bond, and since there are 3 S-O-S bonds, we add 3 more sigma bonds.

Total sigma bonds = 9 + 3 = 12.

**Sigma bonds = 12**

### Step 5: Count pi bonds
In the SO₃ molecule, each sulfur-oxygen double bond consists of one sigma bond and one pi bond. Each sulfur atom forms double bonds with the three oxygen atoms, contributing one pi bond per double bond.

For three sulfur atoms:
- Each sulfur forms 3 pi bonds, so for 3 sulfur atoms:
3 (sulfur atoms) × 3 (pi bonds per sulfur) = 9 pi bonds.

However, since we are only looking for pi bonds in the trimer structure, we need to consider that each double bond contributes one pi bond, and there are a total of 6 double bonds in the trimer (2 from each of the 3 sulfur atoms).

**Pi bonds = 6**

### Final Summary
- S-S bonds = 0
- S-O-S bonds = 3
- Sigma bonds = 12
- Pi bonds = 6

### Answer
The final answer is:
- S-S bonds: 0
- S-O-S bonds: 3
- Sigma bonds: 12
- Pi bonds: 6

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