Some bacteria obtain their energy by oxidising sulphur, producing sulphuric acid as a by-product. In the laboratory, or in industry, the first step in the conversion of sulphur to sulphuric acid is to produce sulphur dioxide. The sulphur dioxide is converted to sulphur trioxide, which reacts with water to give sulphuric acid.
What is the name of the compound formed between sulphur trioxide and sulphuric acid? 

Explanation

To solve the question regarding the compound formed between sulfur trioxide (SO₃) and sulfuric acid (H₂SO₄), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reaction**:
- When sulfur trioxide (SO₃) reacts with concentrated sulfuric acid (H₂SO₄), a new compound is formed.

2. **Identifying the Reaction**:
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