Energies in an atom ( IB Physics - Atomic physics )

[@LECityLECLEC]

Your videos give me energy to learn more about energy physics :D

[@zakirhussain-js9ku]

Excellent video. Both electron and proton have mass so they also possess rest mass energy according to E=MC 2. We understand potential energy of electron since it is in an electric field and KE of electron since it is on motion. How can we visualise rest mass energy of electron and proton?

[@PhysicsMadeEasy]

Well, at the levels of energy of an atom, the rest mass is going to stay as it is, 'inactive' As it is not common to liberate such energy it in a familiar context to humans, there is not much to visualize. If you want , you can see as the energy that a couple of photons would have if the electron disintegrated by meeting a positron. electron + positron --> 2 photons. each photon carrying the energy of an electron: Einstein Energy/mass equivalence: E^2 = m^2c^4 + p^2c^2 , in other words, for a photon, E = pc. With De Brogglie formula p = h/lambda, you end up with E = hc/lambda = hf). So the mass of a particule can be visualized as the frequency of the photon resulting from its annihilation.

[@kisho2679]

How can the energy of any chemical element (= stable atom) be calculated based on its electron configuration (not just only for Hydrogen)?

[@PhysicsMadeEasy]

When calculating the energy of the atom, you need to sum the KE of all the electrons and their individual contribution to the PE. For one given electron, you need to take into consideration the interaction with the other electrons. You cannot do this easily by hand like with the hydrogen, you need a computer... However, there are methods to approximate this by hand. For example, you can apply Slater rules (en.wikipedia.org/wiki/Slater%27s_rules). In this technique, when calculating the energy of an electron sitting on an outer orbital, the positive charge of the nucleus is 'shielded' by electrons in the inner orbitals, and appears weaker. Thus the electron's potential energy is less.

[@zakirhussain-js9ku]

Sir. Proton is made of quarks. Do quarks have energy. Everything in universe is spinning, could Proton be spinning as well. Does Proton provide energy in beta + decay. When protons and neutrons assemble to make nucleus they lose some mass or energy where does this energy come from. From where does binding energy appear in nucleus which is energy deficient due to loss of energy in its making.

[@PhysicsMadeEasy]

So many questions Zakir... could Proton be spinning as well: yes and no... Protons have the quantum equivalent of an angular momentum (Spin). Does Proton provide energy in beta + decay? The energy in beta decay comes from the loss of mass during the reaction. So in a sense yes. When protons and neutrons assemble to make nucleus they lose some mass or energy where does this energy come from?: The nuclear binding energy (energy needed to break the nucleus into its nucleons. Analogy: It's like the saying that there is a loss of energy of the ball when a ball falls to the ground... You need (gravitational) energy to bring it back again... You should check in my channel, the playlist on particle physics (it's a real little course...), I discuss much of this stuff!

[@FahadKhan-uq5nx]

Sir l have a question , substance take part in chemical reaction to acquire the minimum energy state by lowering down the potential energy. What this statement say

[@PhysicsMadeEasy]

When you drop something, what happens? It falls . Why is that? Because of gravity. But why does gravity do that? To lower the gravitational potential energy of the object (lowers PE=mgh, by lowering the height h). You see, the laws of physics (and chemistry) always tend to make things reach a state of lower potential energy. In a chemical reaction also. A chemical reaction that occurs naturally / spontaneously will always lower the chemical energy of the reactants (in your sentence, reactants = the substance that take part in the reaction). Chemical energy is a form of potential energy. I hope this helps, and I wish you good luck with your studies

[@FahadKhan-uq5nx]

@@PhysicsMadeEasy sir , where the potential energy present in atom

[@PhysicsMadeEasy]

@@FahadKhan-uq5nx The potential energy in an atom is electrical potential energy: the nucleus, positively charged attracts the electron negatively charged (like gravity between two masses). For example, if you pull the electron away from the nucleus, you have to work (=tranfer energy to the atom): you increase the potential energy of the atom.

[@gremanonuevo2990]

I do have a question sir, Is inner shell have a higher kinetic energy than the outer shell?

[@PhysicsMadeEasy]

This is correct Grem. The KE energy of the electrons in an inner "shell" will be larger. The potential energy though will be more negative in the inner shell. The magnitude of the change in PE being more than that of KE (assuming circular motion), the total energy of the atom in the inner shell will be more negative. Good question, it gives me the idea for a new video about the amazing relations between KE, PE and TE in circular orbiting system.

[@polokchoaolok2019]

Really very helpful video..Easy to understand.I have a question and it is: Why an atom become static with the lowest potential energy?What does the lowest potential energy refer?

[@PhysicsMadeEasy]

Hi Polok, Potential Energy refers to a system of bodies that interact (i.e. when there is a force between the two bodies). For example, in gravity, when someone says an object has gravitational potential energy because of its height, it is actually not correct, it is the system object/Earth that has potential energy because there is a force between them (that depends on the distance between the Object and the Body). In an atom, the force between nucleus and electron is of an electrical nature, so potential energy refers to the system electron-nucleus, and the force involved is the electromagnetic force. When the potential energy of the atom is the lowest (Ground state), it means that the force between the electron and nucleus is the strongest (logic, they are closer, so the force is stronger). the potential energy will be negative with the highest magnitude (i.e. the most negative). It also means that you will need to provide the maximal energy to separate them: The atom is in its most stable state (ground state, you cannot be more stable than on the ground right ;-)). On the other hand, when electron and nucleus are infinitely far away, the force between them is infinitely small, so the potential energy is zero. Does this answer your question?

[@a.k2767]

You create excellent videos

[@PhysicsMadeEasy]

Thank you Imtiyaz

[@FahadKhan-uq5nx]

Please plzzzzzzzz sirrrrrrrrrrrrrrrrrrrrrrr answer me