What is the aim of Franck Hertz experiment?
The Franck–Hertz experiment was the first electrical measurement to clearly show the quantum nature of atoms, and thus “transformed our understanding of the world”. It was presented on April 24, 1914, to the German Physical Society in a paper by James Franck and Gustav Hertz.
Why was argon used in Franck Hertz experiment?
The use of Argon is preferred because mercury is toxic. In addition, heat is required to vaporize the mercury, but no heat is required for Argon gas. The Frank-Hertz tube used in this lab is a tetrode filled with Argon.
What inference is drawn Franck Hertz experiment?
Conclusions from the plot of Franck and Hertz experiment Rising curve in the current v/s accelerating plot corresponds to region where the electron gain kinetic energy due to excitation potential but not enough to ionize the medium (mercury).
What really happens in the Franck Hertz experiment with mercury?
The electron-mercury collision experiment of Franck and Hertz,¹ for which they won the Nobel Prize in 1925, is one of the key experiments that helped to establish modern atomic theory. It shows that atoms can absorb energy only in quantum portions confirming Bohr’s postulates.
How many electrodes are used in Franck-Hertz experiment?
three electrodes
Experimental Apparatus: The primary apparatus used in this experiment is a vacuum tube constructed with three electrodes (a triode) and containing a small drop of mercury.
What is the role of VG2K in Franck Hertz tube?
The Frank-hertz tube in this instrument is a tetrode filled with the vapour of the experimental substance Fig. 1 indicates the basic scheme of experiment. The electrons emitted by filament can be accelerated by the potential VG2K between the cathode and the grid G2. The grid G1 helps in minimizing space charge effects.
What is first excitation potential?
Hint: The first excitation potential of a hydrogen is the energy released by an electron when it drops from the first excited state to the ground state in the hydrogen atom. The ionization energy is the energy released when the electron comes to the ground state in the hydrogen atom from infinity.
What is the first excitation energy of mercury?
4.92V
The first excitation potential of mercury was found to be 4.92V±0.04V, and that of neon was found to be 19.3V±0.1V.
Why electrons are used to excite atoms?
When an electron temporarily occupies an energy state greater than its ground state, it is in an excited state. An electron can become excited if it is given extra energy, such as if it absorbs a photon, or packet of light, or collides with a nearby atom or particle.
What is the difference between ionization and excitation?
Excitation is the movement of an electron from a lower energy level to a higher energy level by absorbing energy. It makes an atom move from a ground state to an excited state. Ionization energy is the removal of an electron from a neutral gaseous atom.
What was the significance of the Franck Hertz experiment?
In 1914, J. Franck and G. Hertz performed a landmark experiment, providing important empirical support for Max Planck’s quantum theory and for the model of the atom suggested by Niels Bohr.
What did Franck and Hertz discover about the electron configuration of mercury?
However, Franck and Hertz discovered that Ic went through a series of maxima and minima as the accelerating potential was varied. This implies that the gas molecules absorb energy from the electrons only at specific electron energies (resonant energies). For example, the first excited state of mercury is 4.9 eV above the ground state.
What did Franck and Hertz discover about ionic compounds?
However, Franck and Hertz discovered that Ic went through a series of maxima and minima as the accelerating potential was varied. This implies that the gas molecules absorb energy from the electrons only at specific electron energies (resonant energies).
How do I use the Franck-Hertz thermostat tube?
Replace the front panel with the Franck-Hertz Tube as shown in Figure 4. Insert a centigrade thermometer (0-200 degrees) into the hole in the top of the oven. Insert it so the tip of the thermometer is near the center of the tube. Check the label and plug the oven into an appropriate AC power outlet, then turn the thermostat dial to