Helium Emission Spectrum Wavelengths
Introduction:
Helium is a chemical element known for its distinctive emission spectrum. When helium gas is excited, it emits light of specific wavelengths. This phenomenon, called the helium emission spectrum, provides important insights into the atomic structure of helium and has practical applications in various fields.
1. The atomic structure of helium:
Helium is the second lightest element, with an atomic number of 2. Its atomic structure consists of two protons in the nucleus and two electrons in orbit around the nucleus. These electrons occupy specific energy levels or shells designated as the K and L shells. Understanding the arrangement of these electrons is crucial for understanding the helium emission spectrum.
2. The helium emission spectrum:
When external energy is supplied to helium gas, such as through an electric current or a high-energy source, the electrons in the atoms of the gas become excited. These excited electrons move to higher energy levels temporarily and then quickly return to their original energy levels. During this transition, they release energy in the form of light of specific wavelengths.
3. Wavelengths in the helium emission spectrum:
The helium emission spectrum consists of several distinct wavelengths of light. Each wavelength corresponds to a specific energy level transition. Some notable wavelengths in the helium emission spectrum include:
– 388.86 nm (nanometers): This wavelength corresponds to the transition of an electron from the second excited state (2p) to the first excited state (2s). The light emitted at this wavelength appears as violet.
– 447.1 nm: This wavelength corresponds to the transition of an electron from the third excited state (3d) to the first excited state (2p). The light emitted at this wavelength appears as blue.
– 501.57 nm: This wavelength corresponds to the transition of an electron from the fourth excited state (4f) to the first excited state (2p). The light emitted at this wavelength appears as green.
– 587.56 nm: This wavelength corresponds to the transition of an electron from the fifth excited state (5g) to the first excited state (2p). The light emitted at this wavelength appears as yellow.
– 667.815 nm: This wavelength corresponds to the transition of an electron from the sixth excited state (6h) to the first excited state (2p). The light emitted at this wavelength appears as orange-red.
Conclusion:
The helium emission spectrum is characterized by specific wavelengths of light emitted when helium gas is excited. These wavelengths correspond to electron energy level transitions within the helium atom. Understanding and studying the helium emission spectrum allows scientists to gain insights into the atomic structure of helium and use this knowledge in various applications, such as spectroscopy and the study of stellar atmospheres.
