The line spectrum of two elements is not identical because

Options

A. They do not have same number of nuctrons
B. They have dissimilar mass number
C. They have different energy level schemes
D. They have different numebr of valence electron

Answer

**Step-by-Step Solution:**

1. **Understanding Line Spectrum**: A line spectrum is produced when electrons in an atom transition between different energy levels. Each element has a unique arrangement of electrons and energy levels.

2. **Energy Levels in Atoms**: The energy levels of electrons in an atom are determined by the number of protons in the nucleus and the electron configuration. Different elements have different numbers of protons and electrons, leading to different energy levels.

3. **Electron Transitions**: When an electron absorbs energy, it can move to a higher energy level. When it falls back to a lower energy level, it emits energy in the form of light. The wavelength (and thus color) of this light corresponds to specific energy differences between the levels.

4. **Unique Spectral Lines**: Since each element has a unique set of energy levels, the wavelengths of light emitted during electron transitions will also be unique. This results in a distinct line spectrum for each element.

5. **Conclusion**: Therefore, the line spectrum of two elements is not identical because they have different electron configurations and energy levels, leading to different wavelengths of emitted light during electron transitions.

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