A hydrogen atom in a state of binding energy 0.85 eV makes a transition to a state of excitation energy of 10.2 eV . Find the energy and wavelength of photon emitted.

Explanation

To solve the problem, we need to find the energy and wavelength of the photon emitted when a hydrogen atom transitions from one energy state to another.

### Step-by-Step Solution:

1. **Identify the Initial and Final States**:
- The hydrogen atom is initially in a state with a binding energy of \(0.85 \, \text{eV}\). This corresponds to the fourth energy level (\(n=4\)).
- The atom transitions to a state with an excitation energy of \(10.2 \, \text{eV}\). This corresponds to the second energy level (\(n=2\)).

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