A nucleus made of protons and neutrons surrounded by a cloud of electrons equal in number to the protons.

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Electron speed in Atoms

Is the speed of electrons in Atoms consistent in all Atoms or clusters/groups/individual elements, and if it is consistent in any atom, is that speed constant?
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129 views

Are particles solid?

My intuitive understanding is that although atoms are mostly empty space, the nucleus is solid. Thus a neutron or a neutrino can collide with it and do things like deflect or cause a nuclear ...
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779 views

Why is a proton assumed to be always at the center while applying the Schrödinger equation?

Why is a proton assumed to be always at the center while applying the Schrödinger equation? Isn't it a quantum particle?
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24 views

How does beta+ decay actually occur? [duplicate]

I'm having difficulty in understanding beta plus decay. How can a proton which has slightly less mass than neutron transform into a neutron, positron and neutrino? Form where does the extra mass for ...
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1answer
177 views

Do atomic nuclei have fixed orientation and position with respect to the electron cloud?

Does the nucleus of an atom of any element (besides protium) maintain a particular orientation in relation to its electron cloud? Does it bounce around within its cloud? Can it be ejected from its ...
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158 views

Can I excite an already unstable element for accelerated decay?

Say I had an unstable element ready to go through beta decay and I introduced it to high speed electrons: would this lessen the time needed for the product to go through beta decay?
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41 views

Cathode Ray Tube

I am considering the cathode ray tube of the set up, when the cathode rays were discovered Voltage = Very High Gas = any Atmospheric Pressure = We change (In the following example i am just changing ...
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61 views

Molecules and electrons energy types

What are the types of energy that an atom or a molecule could have? For example they have kinetic energy, could they also have other types?
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2answers
79 views

How do you know which atoms are in a specific piece of matter?

If you have a piece of matter in front of you, how can you know of which atoms it consists? And starting from nothing, how can I discover all the elements (or just a lot of them) of the periodic ...
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323 views

Show that the circumference of the Bohr orbit of hydrogen is an integral multiple of the wavelength of the electron in it [closed]

We have an electron revolving in a the $n$th Bohr orbit of an atom of hydrogen. The problem is to prove that the circumference of the orbit is an integral multiple of wavelength of this electron ...
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104 views

What are the assumptions behind “term symbols”?

In multi-electron atoms, the electronic state of the optically active "subshell" is often expressed in "term symbols" notation. I.e. $^{2S+1}L_J$. This presumes that the system of electrons has ...
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122 views

What happens to the atoms and their constituents when we break something ?

My query is: how does an atom stable itself. When we break something, what actually happens in the chemical bonding of its atoms, does it rupture or remain intact?
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Why does amount of protons define how matter is?

My question might sound convoluted but my mind is twisting right now so my apologies in advanced. Why is it that when I have one proton and one electron it is Hydrogen a clear flammable gas, and ...
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2answers
280 views

What is the reason for the electrons in a given subshell to orient in certain preferred regions?

My text book says: "Magnetic quantum number describes the behavior of electron in a magnetic field. We know that the movement of electrical charge is always associated with magnetic field. Since ...
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1answer
1k views

Why is the charge on protons == to charge on electrons? [duplicate]

I am not a expert on physics, just another high schooler, so sorry if the question is obvious. This is something I've been wondering about for a while. Why is the charge on a proton equal but ...
2
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1answer
565 views

Explanation on Atomic Orbitals and Molecular Orbitals

We were reading about atomic structures and bond making and my teacher told me that when two atoms are fused or when they make bond, two orbitals are formed. 1-Bonding Molecular Orbital & 2- ...
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4answers
137 views

Are atoms getting weaker? [duplicate]

If the universe is expanding, it would make sense that the spaces between particles are getting bigger. If this is so, then the particles which make up atoms are also affected. Does that imply the ...
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1answer
59 views

Can there exist a Wave which changes the quantum states of particles?

i'm a high school student and i was reading about electromagnetic waves and how they transport energy and that the electric and magnetic fields sustain each other. I have also read about longitudinal ...
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2answers
2k views

Why do atoms stick together?

The atoms in my table "stick together" to form a rectangle. Why? What makes them stick together? I know about ionic/covalent bonding etc., but consider a sheet of pure iron. Just atoms of one ...
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3answers
207 views

Atoms and electrons?

Consider a copper atom. If you place an electron near it, the protons in the nucleus would attract it like they attract the existing electron in the valence shell. However the electron you placed ...
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1answer
1k views

Is it that electron of an atom can be found anywhere in the space?

Simple pictures showing orbital shapes are intended to describe the angular forms of regions in space where the electrons occupying the orbital are likely to be found. The diagrams cannot, ...
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1answer
46 views

Is there a probability that an electron in an atom change its energy level due to emitting gravitational wave?

Is there a probability that an electron in an atom change its orbital by emitting a quantum of gravitational radiation instead of photon?
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2answers
895 views

Why would an electron in an orbit be accelerating continuously and would thus radiate away its energy and fall into the nucleus in a classical model? [duplicate]

I was reading this answer by madame anna v: You are right, the planetary model of the atom does not make sense when one considers the electromagnetic forces involved. The electron in an orbit is ...
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1answer
49 views

Measuring spin direction by means of coherent light?

Let us assume that we have the ferromagnetic surface where all atoms have the same direction of spins. And we can interact with the single atom in such lattice. Is it possible to measure the ...
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2answers
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The Nucleus of an Atom

We know that the protons in a nucleus are positively charged, whereas the neutrons do not possess a charge; we also know that unlike charges attract. So why does the nucleus stay intact, even though ...
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5answers
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Do electrons collapse into nucleus, if electrons in the atom are constantly excited?

From the Bohr's atomic model, it is clear that electron can have only certain definite energy levels. When the electron is present as close to the nucleus as possible, the atom has the minimum ...
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458 views

How to determine what an object is composed of?

Heads up: This question has never been asked (here) before the way I will ask it here, so let's shed some light on it a bit. Prelude and anecdote(can be skipped): The other day I was walking home, ...
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683 views

Why is the Bohr's idea of defined circular orbits overruled?

If we consider a thought experiment for determining position of an electron by using photons of light. According to principles of optics, if we use light of wavelength $\lambda$, then the position of ...
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1answer
3k views

How can I calculate out the 'specific charge' of an atom? [closed]

I know that it's charge/mass. But what steps do I take to calculate the specific charge of say, carbon-12? What about ions too?
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1answer
1k views

How to determine how many atoms are in something?

I want to know if it's possible to find out how many atoms are in something, and how one would do that. For example, how many quarks are in my brain(easy to find out once you know how many atoms there ...
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2answers
2k views

Doping of pentavalent atom with hexavalent atom

We know that a tetra valent element can be a semiconductor and doping of pentavalent and trivalent impurities would give a extrinsic semiconductor. I got a question now. Can we use an element of ...
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2answers
467 views

Why and how, in QED, can excited atoms emit photons?

The quantum mechanics of the structure of atoms as determined by the electromagnetic forces inside them correctly describes the location and coupling of the different energy levels in essentially all ...
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142 views

Is the relative atomic mass directly proportional to the size of an atom? [closed]

I have a piece of homework, i have to make a pair of models depicting pure metals and alloys. I want it to be as accurate as possible, and so i'm asking this: Is the relative atomic mass directly ...
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2answers
193 views

Do atoms get created or are they recycled?

Basically, are the atoms that make up my body right now something that has existed since the big bang?
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1answer
211 views

Seeing inside an atom

After seeing this photograph and reading this article : The First Image Ever of a Hydrogen Atom's Orbital Structure I was really happy to come to know that orbitals have actually been seen now, but ...
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1answer
200 views

How much lead is there in the universe?

I know there is around 10^80 atoms in the observable universe, but is there any estimate the amount of lead in the universe (within a couple magnitudes of 10)?
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321 views

Which is more characteristic of an element absorption or emission spectrum?

Absorption and emission spectrum are used to reveal the identity of an element and even to find new elements. But, which of them is more characteristic? The mission spectrum would have more lines ...
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Absorption from a classical to quantum

Today, I learned that using rubidium atoms at very low temperature in a Magneto-optical trap, one can experimentally show that the Lorentz classical derivation of absorption using dipole is valid. The ...
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5answers
564 views

Do orbitals overlap?

Yes, as the title states: Do orbitals overlap ? I mean, if I take a look at this figure... I see the distribution in different orbitals. So if for example I take the S orbitals, they are all just ...
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1answer
668 views

In truth, only atoms and the void

I have a question about this motto used by Sean Carroll in his blog: In truth, only atoms and the void. Can you explain what this sentence means? My interpretation is that the sentence does ...
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38 views

Factors defining interaction between atoms and molecules

Let's say we have a stuff that consists only of hydrogen (H), then we add a single atom of oxygen (O) and they interfere - we get a water molecule where atoms are arranged in a particular way. Then we ...
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2answers
2k views

Difference between spin-orbit coupling and LS coupling (Russell-Saunders)

I'm having some trouble understand what the difference is between these two. It seems as though there are kind of the same, but that spin-orbit coupling reduces to LS coupling under certain ...
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1answer
172 views

What is the pressure of a gas required to ionize the gas using an electron gun?

How dense does a gas (Argon in particular ) have to be to in order to ionize it using electron bombardment and weak magnetic fields. Is there a correlation with the density of a gas and the easiness ...
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448 views

Relation between decay probability and the energy of particle

Is there any way to find the energy of a particle through its decay probability?
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3answers
210 views

Could I use an electron gun to make plasma?

Could I ionize a gas using an electron gun and knock off electrons in the gas to make plasma?
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381 views

Do inner shell electrons feel the electric field/force from an outer shell electron in an atom?

We just finished studying Gauss’ law and were puzzled by this thought. If I look at a copper atom and focus on the 29th electron in the 4th shell, according to Gauss’ law, I can draw a Gaussian ...
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2answers
545 views

Why do smaller objects become harder to break?

When grabbing a typical tree branch of at least two feet, it's so easy to snap with a less than one inch circumference that even a toddler can do it. However, after breaking it, the smaller halves ...
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237 views

LS Coupling - weird image in the book

In the book by Arthur Beiser, Concepts of modern physics, in the chapter LS coupling there is this image: QUESTION: How do we get total orbital angular momentum $L=3$ (image (a)) out of quantum ...
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1answer
161 views

How do I find the amount of atoms in a pure gas in a confined area?

Say I have Argon gas in an area such as a cube with pressure around pressure between 10-5 and 10-3 Torr (pressure) at 25 degrees at 320 Kelvins . How do I find the amount of atoms in that cube? Any ...
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1answer
99 views

What methods exist for us to measure the position and momentum of atoms that make up molecules?

In this paper, Localization of an atom by homodyne measurement. A. M. Herkommer et al. Quantum Semiclass. Opt. 8 no. 1, p. 189 (1996) (paywalled). the authors are able to localize atoms using ...