What is the use of platinum foil in the hydrogen electrode ?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Hydrogen Electrode**: The hydrogen electrode is a type of electrochemical cell that serves as a reference electrode. It consists of a platinum electrode in contact with hydrogen gas at a pressure of 1 atm and immersed in a solution of hydrogen ions (H⁺).

2. **Role of Platinum Foil**: The platinum foil is used in the hydrogen electrode primarily due to its properties as a noble metal. Being a noble metal means that platinum is resistant to corrosion and does not react easily with other substances.

3. **Facilitating Electron Transfer**: The platinum foil allows for the inflow and outflow of electrons during the redox reactions occurring at the electrode. It acts as a conductor, facilitating the movement of electrons between the hydrogen gas and the electrolyte solution.

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