114 學年度臺灣大學轉學生招生考試｜第 62 題
普通物理學(A)
- A molecule does not have spectral lines due to electron changing energy levels.
- A molecule has additional spectral lines due to changes in its rotational and vibrational energies.
- Molecules only have spectral lines at ultraviolet wavelengths.
- Most atoms only have spectral lines at infrared wavelengths.
- An atom has a wider range of spectral lines than molecules.
提示
Atoms store energy only in electronic transitions. Molecules have extra internal degrees of freedom that produce additional sets of lines and bands.
正確答案
正解：B
詳解
A. (A) — incorrect. Molecules still have electronic transitions just like atoms; they do not lose them.
B. (B) — correct. Beyond electronic transitions, molecules can also change their rotational and vibrational energy states. These quantized rotational and vibrational levels add many extra lines (and band structure), which atoms — having no such internal motions — lack.
C. (C) — incorrect. Molecular spectra are not confined to ultraviolet; rotational lines lie in the microwave/far-IR and vibrational lines in the infrared.
D. (D) — incorrect. Atomic spectral lines are not generally restricted to infrared; this is a false generalization.
E. (E) — incorrect. It is the reverse: molecules have a richer, wider set of lines than atoms because of the added rotational and vibrational structure.
