Atomic Definition and 853 Threads

The first light atomic nucleus with a second face Physicist found the first light atomic nucleus in a lab that had too little resources. http://sciencefeeds.weebly.com/journal/the-first-light-atomic-nucleus-with-a-second-face

I am trying to learn quantum physics on my own and while doing this I came across bohr's atomic model. What parts should I focus on the bohr's atomic model so advancing to schrodinger's equation will be easy?

Let's say there are three states ofor energym, E1, E2 and E3, and the electron is at E1, what happens if a photon has energy E > E2-E1 ? Does it interact to the electron anD take it to E2 and the photon loose energy E2-E1 or it doesn't interact at ALL? I mean, the electron can't have an energy...

I believe that this question may be solved by the John Dalton ratios, but, I'm confused: While traveling to a distant universe, you discover the hypothetical element “X.”You obtain a representative sample of the element and discover that it is made up of two isotopes,X-23 and X-25. To help your...

I recall hearing somewhere that the official length of a second was now kept by the measure of how much an atom of a certain material or isotope decays, such as "When X decays by Y it equals one second" For the novel I'm writing I need a means to measure seconds that would be completely...

Normally, I prefer to do my own research, but I'm drawing a blank on this one. Any help would be appreciated. My understanding is that statistical mechanics accounts for all of the heat energy in a gas by the kinetic energy of the molecules. I also understand that atomic orbitals have different...

My question is the following one: If i have the first excited state of helium, the possibilities for the two electrons are : 1s+,2s+ , 1s+2s-, 1s-,2s- and 1s-,2s+ , where + and - denotes spin up and down. If I use the slater's determinant to generate antisymmetric states, I get : $$|u1> =...

Hello, I need same help with the following exercise: (1a)Recall Ehrenfest’s theorem and state the conditions for classicality of the trajectory of a quantum particle. (1b) Consider an atom whose state is described by a wavepacket with variance ∆x^2 in position and ∆p^2 in momentum. The atom...

Homework Statement Consider an electron in a state described by angular wavefunction $$\psi(\theta,\phi)=\sqrt{\frac{3}{4 \pi}}\sin \theta \cos \phi$$ Here θ and φ are the polar and azimuthal angles, respectively, in the spherical coordinate system. i. Calculate the probability that a...

Sorry if this question has been asked before or is common knowledge. It seems to me that when one or more electrons in an atom is excited to a higher energy state, then the effective potential experienced by other electrons should be different from the potential in the ground state. Hence the...

When we say that a phonon vibration mode has an average energy <E> are we saying that all atoms (or harmonic oscillators) in a piece of matter (eg. a nanoparticle) will also has that energy, or that the piece of matter as a whole will have that energy ? In the second case the amplitude of the...

I have a complete brain freeze sorry, and cannot work this out. I have a helium atom of 4.0 amu and there are 6.0 x 10^24 atoms. How do I calculate the total mass in kg please? Thanks

I've seen the equation I think is just for hydrogen. is this just for hydrogen? of course this doesn't return the atomic spectra, it returns the energy. So using E=h*v and Planck's constant. a simple factor of 1/h would return the frequency. right? Energy is directly proportional to frequency...

I'm trying to deduce the weight of 1 atomic mass unit (##1u##) in ##kilograms## from the following scenario: One atomic mass unit is 1/12 of the weight of a ##^{12}C## atom in its ground state. A ##^{12}C## atom consists of 6 protons, 6 neutrons and 6 electrons. This means that $$1u =...

Steven Weinberg has lately been critical of QM. He now also has a technical paper out called 'Lindblad Decoherence in Atomic Clocks', available on arxiv. Here is the abstract: It's a short paper (6 pgs of text), arguing for objective collapse (a la GRW/Diosi-Penrose/etc) instead of...

I was just wondering if anyone new approximately how many AMO physics departments existed. Because I know that not every school has one. I was disappointed when I found out that my school doesn't have one. Thanks.

I was watching an explanation (found here: youtu.be/yTkojROg-t8 ) on nuclear fission. In the video, he described the process of fission to happen one a random neutron smashes into a uranium nucleus. This causes the necleus to split into krpyton and barium, taking part of the nucleon and...

I read that a hollow cathode lamp is preferable to a continuum light source since it emits a sharp atomic spectrum and hence the noise is lower. Could someone please explain how the noise is affected by the sharpness of the atomic lines? Also would you expect only the colours corresponding to...

< Mentor Note -- thread moved to HH from the technical physics forums, so no HH Template is shown > Hello mates. I was wandering how to analyze an atomic bomb, when the only information given, is that the bomb contains 5,6 kg plutonium, and is the same model as fat man. Do you have any...

I have a simple doubt to keep things clear. Why doesn't electrons fall into the nucleus of an atom? Is it because of the high velocity of electrons? If so, at what velocity will the electron be slow enough to collapse into the nucleus?

So I just had a question about calculating moles atomic iodine when you have the moles of molecular iodine. In the chemical equation IO3-(aq) + I-(aq) + H+(aq) = I2(aq) + H2O(l) Would the moles of atomic iodine be equal to the moles of the molecular iodine? or would the moles of atomic iodine...

"What are the imperfections in the atomic arrangements that have a significant effect on the material behavior? Give an example of each." Can someone please explain to me what these imperfections are and why they have a significant effect? This question is from section 4.7, number 49 of this...

The following mechanism leads me to wander that a moving neutral object (compose from atoms) in vacuum may generates electric filed due to very small dipole moment. I propose that when atoms force to move in a certain direction the force propagates within the atom. A retardation in movements...

Does the shape of atomic orbital changes when exposed to electric or magnetic field?

A few quick questions I'd like cleared up:1) Alkali metals are said to have a really low threshold energy, enough for visible light to cause the photoelectric effect. Does this mean if I aim a flashlight (turned on) at a piece of sodium, I could ionise it? Simply flashing a light over a piece of...

I've been thinking... Is there any way that there could be sort of a one-time use pulse laser that uses something like a mini atomic bomb to create a super high energy laser? I found stuff about a Nuclear pumped laser and "Project Excalibur", but I wanted to ask actual people who know a lot...

Does 1 mole of any given element,the same size as that of one mole of any other element of the same period of the modern periodic table

It’s commonly held that left and right photons interact with matter in exactly the same way, because electromagnetism “conserves parity”. But we know that P-symmetry, in our world, is generally broken. Even according to the Standard Model, when light propagates through some media, it interacts...

The atomic clock is used as evidence of time dilation and to provide more evidence that light speed is invariant. The problem I have with this is that the clock uses frequency and light. It has a feedback loop that is supposed to correct for inaccuracies but the entire loop will obviously be...

My understanding is that matter tends to converge and form stars and in those stars fusion creates heavier atoms from lighter atoms, and this process repeats continuously. if this is true wouldn't it imply that throughout these star cycles the average atomic mass will just increase, and as the...

To calculate the Keldysh parameter, I need to use the optical frequency of a laser in atomic unit. Since for the time: 1 a.u. = 2.42×10-17 s, I would assume that for the frequency: 1 a.u. = 4.13×1016 s-1 which is juste the inverse of the time one. However, I found several sources such as...

I am still in secondary school so I probably shouldn't think about things this complicated (at least that's what it seems to me, complicated), but please correct me if I'm wrong. If I recall correctly, the position of an electron is never certain, and always based on probability, unless...

The Hamiltonian of an atomic electron is spherically symmetric so we expect to have symmetric distribution of electrons around the nucleus. However, as an example, p-orbitals don't have spherical symmetry and p_x-orbitals imply that electrons may be found in the x-direction with higher...

I've been recently trying to understand the concept of paramagnetism, but I feel like I'm running into 2 conflicting models. Stern–Gerlach seems to suggest that electron spins always point up or down to an incident magnetic field, regardless of their spatial orientation. Similarly, when...

Homework Statement Suppose the element A contains three isotopes, 86A (atomic mass 85.909 u, abundance 16.19%) 87A (atomic mass 86.908, abundance 7.00%) and 88A (atomic mass 87.906 u). What would be the atomic mass of A that would appear in the periodic table? Homework Equations (A1 x %A1) +...

Homework Statement "You might wonder how six protons and six neutrons, each having a mass larger than 1 u, can be combined with six electrons to form a carbon-12 atom having a mass of exactly 12 u. The bound system of carbon-12 has a lower rest energy than that of six separate protons and six...

If like charges repel each other, what keeps the protons clustered in the nucleus of the atom from separating ? and why wouldn't the electrons with a negative charge pull them out from the nucleus ?

Consider a piece of pure Fe hot enough to have a bright white color (about 2 000 ºC, e.g.) and the characteristic yellow narrow yellow emission of the Na atom. Does the Na yellow band will be present at the thermal spectra of the pure Fe? My guess: Yes.

Homework Statement Hi! I have a a question regarding the Atomic Spectra of Hydrogen and Mercury. My problem involves the value of m and Rydberg's constant. I used a spectrometer for this lab and calculated all the necessary angles. Homework Equations See below The Attempt at a Solution...

Homework Statement An atom with an excited-state configuration 1s22s22p63s23p64s23d14p1 With residual electron-electron interactions are taken into account, this configuration splits into atomic terms. List these terms labelled by their L and S quantum numbers Homework Equations L=|l1-l2|...

Scientists have measured both the blackbody spectrum and also the atomic spectra of various elements in the Sun. How do they distinguish between the two and filter out the light from either one?

For the uncertainty about relative atomic mass. Such as for H-1 there is 1.00794(7)u. what exactly does the "7"means? Is it 1.007947? or 1.00794(+/-)0.000007? or something else? ref: http://www.ciaaw.org/pubs/TSAW-2007.pdf

Beam standard atomic clocks work by changing the magnetic state of a cesium atom by applying a microwave frequency that matches the resonant frequency of a cesium atom. What is this resonant frequency of the atom in terms of actual events that occur on the atomic level...

Homework Statement Hello, This week I ran an AA Spectroscopy experiment in my university, in which we had to analyze the percentage of Copper in a metal coin, and the containment of Iron in morning cereal. We used 2 standard solutions of 1 and 10 ppm (containing both Copper and Iron), and...

1. I understand an expanding gas has increasing entropy and at a cosmic scale the universe is an expanding gas...sort of. 2. back before the universe was cool enough to form atoms it would seem to be very disordered, ie a high temperature universe of a plasma made of nuclei and elementary...

i know this might seem as a very simple question , but i am confused : in order to calculate the total number of vacancies we need the total number of atomic sites N , and since N depends on the density of the material , then N refers to the number of atoms , right ? what confuses me is the word...

As far as I know first entanglement experiment used polarization entangled photons from atomic cascade. As I understand atomic cascade produces entangled photons from two electrons that emit photons by falling from the same orbital to the same lower orbital (so they have the same spin). Now it...

If a magnet is cut in half, it is still a magnet (dipole). If the magnet is continuously cut in half until it is only an atom, it still remains a magnet. My question is, what part of the atom generates the magnet field? I understand that magnets form primarily from the spin and angular momentum...

Hi everyone. On March 11th 2016, there were reports of an alleged coolant leak at the kakrapar atomic power station. The reactor is an Indian PHWR. Articles at the time suggested the first trip on the reactor was high containment pressure, which signaled to me some sort of loss of coolant...

Dear all, So I have a question concerning atomic conservation in an ionized hydrogen gas. So imagine we have ## H_2 ## initially. Later the gas is taken to an appreciable temperature such that at equilibrium the following species are present, ## e^-, \ H, \ H^+, \ H_2, \ H^-, \ \text{and} \...