What is a hydrogen discharge tube?
A hydrogen discharge tube is a slim tube containing hydrogen gas at low pressure with an electrode at each end. If a high voltage (5000 volts) is applied, the tube lights up with a bright pink glow. If the light is passed through a prism or diffraction grating, it is split into its various colors.
What kind of spectrum is emitted by the hydrogen gas tube?
Emission Spectrum of Hydrogen. When an electric current is passed through a glass tube that contains hydrogen gas at low pressure the tube gives off blue light.
How is the atomic spectrum of hydrogen obtained?
Answer: The high voltage in a discharge tube provides that energy. Hydrogen molecules are first broken up into hydrogen atoms (hence the atomic hydrogen emission spectrum) and electrons are then promoted into higher energy levels.
Why does hydrogen spectrum have 4 lines?
This is explained in the Bohr model by the realization that the electron orbits are not equally spaced. The electron energy level diagram for the hydrogen atom. He found that the four visible spectral lines corresponded to transitions from higher energy levels down to the second energy level (n = 2).
Why use a discharge tube instead of a light bulb?
the helium is used instead of a light bulb because a certain element only emits certain wavelengths of light while the bulb would emit all wavelengths, and even if you were to split this with a prism you would still see all the colors and not specific ones.
Why are the spectra for each element unique?
There are many possible electron transitions for each atom, and each transition has a specific energy difference. This collection of different transitions, leading to different radiated wavelengths, make up an emission spectrum. Each element’s emission spectrum is unique.
What is wrong about atomic spectrum of hydrogen?
Answer: The number of lines does not equal the number of electrons in an atom. For example, hydrogen has one electron, but its emission spectrum shows many lines. Hence, the photons of an emission spectrum represent a variety of possible energy levels.
What are the colors in the emission spectrum of hydrogen?
Wavelength Color 656.2 red 486.1 blue-green 434.0 blue-violet 410.1 violet Four more series of lines were discovered in the emission spectrum of hydrogen by searching the infrared spectrum at longer wave-lengths and the ultraviolet spectrum at shorter wavelengths.
How does the Bohr model explain the spectrum of the hydrogen atom?
Niels Bohr proposed a model for the hydrogen atom that explained the spectrum of the The Bohr modelwas based on the following assumptions. The electron in a hydrogen atom travels around the nucleus in a circular orbit. The energy of the electron in an orbit is proportional to its distance from the nucleus.
When does hydrogen atom fall into a lower energy orbit?
According to the Bohr model, the wavelength of the light emitted by a hydrogen atom when the electron falls from a high energy (n = 4) orbit into a lower energy (n = 2) orbit. Substituting the appropriate values of RH, n1, and n2 into the equation shown above gives the following result.
Why do hydrogen atoms emit at a limited number of frequencies?
The fact that hydrogen atoms emit or absorb radiation at a limited number of frequencies implies that these atoms can only absorb radiation with certain energies. This suggests that there are only a limited number of energy levels within the hydrogen atom.
