Question 1: What differences can you think of between the photon and electron?
Answer: Electron is considered as a fundamental sub-atomic particle. It is electrically charged and has a rest mass of 9.11 x 10 -31 kg. Electrons are believed to be identical particles. It is part of the atom. Photons, on the other hand, are more likely defined as a bundle of energy. It is considered as a quantum instead of a sub-atomic particle. Photons are electromagnetic and are always in motion. It has the constant velocity of 2.9799 x 1018 m/s which is approximately the actual speed of light. Unlike the subatomic particles, photons have zero rest energy and mass. However, since photons are observed to be always in motion, it is believed to carry energy and possess momentum. It is also identified to posses particle-like character since it collide with particles like electron but are more taken to be wave-like since it demonstrates frequency and wavelength properties.
Question 27: The Bohr Theory permits us to visualize the structure of the atom, there as, Quantum Mechanics is very complex and concerned with ideas such as wave factions and probabilities. What reasons could lead to the replacement of Bohr Theory by Quantum Mechanics?
Answer: Bohr’s atomic model shows that the atom is composed of three smaller particles wherein the positively charged particle known as proton and the neutral particle or neutron composed the nucleus or the centre of the atom by which an electron or a set of electron revolves in special orbits. Bohr Theory creates the rule that in an atom there is only one electron in each orbit, nonetheless, Bohr also emphasize that the electron can jump between the orbits. Quantum mechanics on the other hand, was established to look into quantum particles that are known to exist in atoms with the introduction of wave-like properties that are found in photons. Quantum mechanics could lead to the replacement of Bohr’s theory as it tries to reveal the behaviour of sub-atomic particles in amore detailed and critical level. However, since Bohr’s theory is essential to introduce the basic concepts of atoms, there is nothing wrong if it is still use in introductory physics. Nonetheless, when applications of physics are concerned Quantum physics is more appropriate. Bohr’s theory can be totally replaced by Quantum mechanics when electrons are proved to be not as identical as formerly explained by Bohr’s theory and when other parts of the Bohr Theory regarding special orbits are proved to be wrong.
Question 28: What Physical qualities are governed by the quantum number of an atomic electron?
Answer: The quantum numbers of an electron denotes the different physical qualities. The principal quantum number refers to the distance between the electron and the nucleus. It is commonly known as the shell to which the electron belongs. The azimuthal quantum number denotes the angular momentum which influences chemical bonds. It is also called the subshell or the orbital number. The magnetic quantum number describes the orbital angular momentum or simply the energy shift. Lastly, the spin projection quantum number or simply the spin of an electron which is either ½ or -1/2 refers to the polarity of the electron.
McMahon, D. (2006). Quantum Mechanics Demystified. McGraw-Hill.
Whitaker, A. (1996). Einstein, Bohr and the Quantum Dilemma. Cambridge University Press.