Why line spectra is regarded as the fingerprints of atoms ?

Explanation

### Step-by-Step Solution:

1. **Definition of Line Spectra**:
- Line spectra refer to the emission or absorption of light by atoms at specific wavelengths. When an atom is energized, it can emit light, and this light consists of distinct lines at particular wavelengths, rather than a continuous spectrum.

2. **Unique Emission for Each Element**:
- Each element has a unique electronic structure, which means that the energy levels of electrons in different atoms are different. As a result, when electrons transition between these energy levels, they emit or absorb light at specific wavelengths that are characteristic of that element.

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