Some elements produce distinct colors in a flame. What is the cause of this phenomenon?

• A. The heat of the flame causes the elements to melt and emit colored light.
• B. The elements react with oxygen in the air to form colored oxides.
• C. Electrons in the atoms absorb energy and move to higher energy levels, then release energy as light of specific wavelengths when they return to lower energy levels.
• D. The color is due to impurities present in the sample.

Answer: (C)

Verified step by step guidance

1. Understand that when elements are heated in a flame, their atoms absorb energy, causing electrons to move from lower energy levels (ground state) to higher energy levels (excited state).
2. Recognize that these excited electrons are unstable and will eventually return to their original lower energy levels.
3. When electrons return to lower energy levels, they release the absorbed energy in the form of light.
4. The wavelength (and thus the color) of the emitted light corresponds to the energy difference between the excited and lower energy levels, which is unique for each element.
5. Conclude that the distinct flame colors are due to these specific electronic transitions in the atoms, not due to melting, chemical reactions, or impurities.