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

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1answer
49 views

Angular momentum Bohr's model

I have been trying to derive speed, radius etc. in hydrogen atom using Bohr's postulates and not neglecting the coulombic attraction on proton. I know that they will be revolving around their centre ...
1
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1answer
105 views

How much smaller will be human body, when we hypothetically get of every space between particles [closed]

I had an interesting dream, where advanced civilization compress their body with technology, that turn off space betweens atoms/particles. They travel in small spaceship with billions citizens very ...
0
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3answers
43 views

In what form does proton give energy to electron?

According to Bohr, electron revolves around the nucleus because of force of attraction between electron and proton. This force of attraction gives energy to the electron. So my question is this that- ...
2
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1answer
123 views

Smallest possible object made of atoms that is spherical to a given degree [closed]

I recently saw a video, World's Roundest Object, which discussed a sphere made of silicon-28. The researcher in the video stated, if the object was scaled to the size of the Earth, the highest and ...
0
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1answer
139 views

Electron Decay, Why are there P and higher orbitals?

Related: Decay from excited state to ground state My confusion arose initially from the definition of binding energy being the lowest energy state (n=1) in the hydrogen atom. This, I assume, is ...
2
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1answer
57 views

Atomic transitions and density: clarification

A laser passes though a cell containing vapor of an alkaline element which causes atomic transitions. I was told that the formula for the atomic density in a Rubidium cell, for example, is given by: ...
1
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0answers
26 views

An EM problem of polarized sphere

Today, I'm doing an EM problem and my question is exactly the same as this site shows: http://www.physicsforums.com/showthread.php?t=133501 To reiterate my confusion, why we can't use that integral ...
0
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3answers
145 views

question on dipole moment of water molecule

I read a line today and don't get it: "Molecules with mirror symmetry like oxygen, nitrogen, carbon dioxide, and carbon tetrachloride have no permanent dipole moments." ...
0
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0answers
25 views

Rutherfords alpha scattering conclutions? [duplicate]

Please can some one give me rutherfords observations and his conclutions from each onbservation, I have looked in text books but they only give them sepratly with no direct link betweeen which ...
2
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1answer
95 views

The position of center of mass of electron cloud in an atom

I read Griffiths EM today and it says something very interesting but a little bothering to me. It states for an atom, the position of center of mass of an electron cloud lies in the center of the ...
0
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1answer
148 views

Expectation value of energy from the position state of hydrogen atom [closed]

I was given with the position state of hydrogen atom: $$ R_{21} =\left(\sqrt{\frac{1}{3}}Y^0_1 + \sqrt{\frac{2}{3}}Y^1_1\right) $$ I am getting confused about getting the expectation value of ...
6
votes
1answer
744 views

Is Palladium an exception?

I have been taught in school that atoms cannot have more than 8 electrons in the outer shell. Palladium atom's electron configuration is 2,8,18,18. Why isn't it 2,8,18,17,1 like the case of Platinum ...
18
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3answers
2k views

What really cause light/photons to appear slower in media?

I know that if we solve the maxwell equation, we will end up with the phase velocity of light is related to the permeability and the permittivity of the material. But this is not what I'm interested ...
0
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1answer
171 views

Why electrons get excited? [closed]

Why and how are electrons get excited and what happen inside an atom when electrons get excited?
1
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2answers
70 views

Quarks are now considered to be fundamentals, but so were atoms some time ago. So the way we see is only limited by our technological advances? [duplicate]

After watching this FuseSchool - Global Education episode, I cannot stop thinking how can something not have a substructure, how it cannot be split? http://www.youtube.com/watch?v=nlv06lSAC7c
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1answer
84 views

How do magnetic objects exhibit attraction/repulsion across empty space?

Magnets will attract or repel over a distance before physically touching each other. What makes this effect possible? My best guess is that the forces generated by the angular momentum of the ...
4
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2answers
110 views

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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2answers
90 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 ...
5
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3answers
682 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?
1
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0answers
21 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 ...
3
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1answer
151 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 ...
-4
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2answers
459 views

What really is the smallest “mass” or “object” in the universe?

Look at this here. With respect to the sciences, the atom is obviously not the smallest piece of mass. Apparently, if people have already broken down the atom in to particles smaller than so, why ...
3
votes
2answers
135 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?
2
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0answers
37 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 ...
31
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4answers
4k views

Are atoms unique?

Do atoms have any uniquely identifying characteristic besides their history? For example, if we had detailed information about a specific carbon atom from one of Planck's fingerprints, and could ...
1
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2answers
56 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?
2
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2answers
65 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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0answers
163 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 ...
2
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0answers
92 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 ...
0
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2answers
88 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?
9
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4answers
2k views

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 ...
2
votes
2answers
152 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 ...
0
votes
1answer
205 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
votes
1answer
409 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- ...
4
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4answers
119 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 ...
2
votes
1answer
56 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 ...
3
votes
2answers
684 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 ...
0
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3answers
136 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 ...
2
votes
1answer
391 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, ...
0
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1answer
40 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?
0
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2answers
421 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 ...
3
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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 ...
5
votes
2answers
924 views

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 ...
0
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5answers
685 views

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 ...
3
votes
2answers
236 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, ...
14
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8answers
2k views

Where did Schrödinger solve the radiating problem of Bohr's model?

One of the problems with Bohr's theory to describe the hydrogen atom, was that the electron orbiting around the nucleus has an acceleration. Therefore it radiates and loses energy, until it would ...
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4answers
333 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 ...
0
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1answer
1k 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?
1
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1answer
331 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 ...
7
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3answers
646 views

What is the quantum mechanical explanation of the octet rule?

What is the quantum mechanical explanation of the octet rule? In other words, what makes the octet rule be true from a quantum mechanical view? How we explain what makes some atoms don't follow the ...