Why is it important to have clean surface in surface studies ?

Explanation

### Step-by-Step Solution:

1. **Understanding Surface Studies**: Surface studies involve the examination of phenomena that occur at the interface between different phases, such as solid-gas, solid-liquid, or solid-solid interfaces. The properties and behaviors at these surfaces can differ significantly from those in the bulk material.

2. **Importance of Clean Surfaces**: A clean surface is crucial in surface studies because impurities or contaminants can interfere with the observations and measurements. If the surface is not clean, it may lead to misleading results or an inability to accurately observe the phenomena of interest.

3. **Focusing on Adsorption**: One key surface phenomenon is adsorption, which is the accumulation of molecules (like gases) on the surface of a solid. For instance, if nitrogen gas (N2) is to be adsorbed on a platinum surface, the presence of dirt or other gases can hinder this process.

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