What are homogeneous catalysts? state one example

Answer

### Step-by-Step Solution:

1. **Definition of Homogeneous Catalysts**:
- A homogeneous catalyst is defined as a catalyst that exists in the same phase (state of matter) as the reactants in a chemical reaction. This means that if the reactants are in a gaseous state, the catalyst must also be in a gaseous state; if the reactants are in a liquid state, the catalyst must also be in a liquid state.

2. **Characteristics**:
- Homogeneous catalysts facilitate reactions by providing an alternative reaction pathway with a lower activation energy. They are typically involved in reactions where all components are mixed uniformly.

3. **Example of a Homogeneous Catalyst**:
- One common example of a homogeneous catalyst is nitric oxide (NO) in the oxidation of sulfur dioxide (SO2) to sulfur trioxide (SO3).
- The reaction can be represented as:
\[ 2 \text{SO}_2(g) + \text{O}_2(g) \xrightarrow{\text{NO}} 2 \text{SO}_3(g) \]
- In this reaction, both sulfur dioxide and oxygen are in the gaseous phase, and nitric oxide acts as the catalyst, also in the gaseous phase.

### Summary:
- Homogeneous catalysts are those that are in the same phase as the reactants. An example is nitric oxide (NO) which catalyzes the oxidation of sulfur dioxide (SO2) to sulfur trioxide (SO3).

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