Questions tagged [atomic-structure]

For questions about the various atomic structure theories, including the Bohr theory. Not to be confused with the actual arrangement of atoms in macroscopic solids ([solid-state-chemistry]) or newer quantum concepts ([quantum-chemistry])

Filter by
Sorted by
Tagged with
27
votes
4answers
3k views

Do electrons have some volume, area or shape?

I am in 8th grade now and when I was in 6th grade, my science book had diagrams of the electronic configuration of atoms. The electrons were round like spherical balls. Is it true that the electrons ...
11
votes
1answer
155 views

Cause of uniform glow in cathode ray tubes

I got the following extract from a chemistry book (emphasis mine): It is observed that current does not flow through the gas at ordinary pressure even at high voltage of 5000 volts. When the ...
7
votes
2answers
111 views

How is the potential energy between two atoms measured?

In class, we learned about the interatomic potential graph. How does one actually measure the potential energy between two atoms experimentally to ensure the graph is correct? What device is used?
6
votes
1answer
60 views

How does de Broglie actually prove Bohr's postulates?

We know Bohr said that the angular momentum of an electron is an integral multiple of $nh/(2π).$ And in de Broglie's wave equation, he said the circumference of the path of the electron traveling as a ...
6
votes
2answers
324 views

Why is there an orbital angular momentum if the electron isn't properly revolving around the nucleus?

I'm a tenth grader who's just been introduced to this subject of atomic structure, so please help. I recently read that an electron doesn't have circular motion around a nucleus, its motion is kind ...
5
votes
1answer
136 views

What happens to the first ionization potential when a hydrogen-like atom captures a particle?

This is a textbook problem from Resonance DLPD Physical Chemistry, Page #83: The mass of a proton is $1836$ times the mass of an electron. If a subatomic particle of mass $207$ times the mass of an ...
5
votes
1answer
167 views

Why the term 'unified' in “unified mass unit”? [closed]

Why different unit symbols - amu, u and dalton are used for representing atomic mass? And what does the term 'unified' mean in "unified mass unit"? Thank you.
4
votes
1answer
312 views

What is the exact definition of the radial distribution function?

I have been very confused by the radial distribution function which is often used in chemistry to predict the probability of finding an electron at a distance from the nucleus. From Atkins' Physical ...
4
votes
1answer
293 views

In Bohr's model what is angular momentum in the lowest orbital?

Angular momentum is given by: $n\frac{h}{2\pi}$ where $n=1,2,3...$ And angular momentum is also given by: $\sqrt{l(l+1)}\frac{h}{2\pi}$ By the first equation angular momentum should be $\frac{h}{2\...
4
votes
2answers
3k views

How do we find the angular, radial nodes and the quantum numbers when the radial probability distribution curve's equation is given?

I am having serious conceptual issues with the Schrödinger equations. Please note that I only have basic school level (11th grade) knowledge of these equations and we are expected to know very little ...
4
votes
1answer
146 views

Volume of orbitals

As I was learning about atomic structure, the lecturer made a seemingly dubious claim: The volume of a p orbital is one-third that of the s orbital. Thus, inter-electronic repulsions are ...
4
votes
2answers
96 views

Is there a finite number to the possible state of electron in an atom?

Okay, I know you may say, there are infinite numbers of possible state of an electron between its ground state and ionic state, since energy levels get continuous as electron gets farther away from ...
3
votes
3answers
94 views

Bohr's model of an atom

This question is not very mighty. But I'm having a problem wrapping my head around the Bohr's atomic structure. The textbook says electrons revolve around the nucleus in fixed energy shells, with each ...
3
votes
2answers
79 views

Atomic weight = expected weight?

The atomic weight of an element, is it accurate to say that another way to think of it is the expected value of that element's weight if we were to sample one at random from the environment? Are man-...
3
votes
2answers
382 views

For hydrogen like atom, find velocity from potential energy

PE of system is given by $$\mathrm{U(r) = \frac{-Ke²}{r^3}}$$ assume bohr model to be valid Find velocity For this I used $\mathrm{\frac{-PE}{2} =KE}$ and then used $$\frac{mv^2}{2} =\frac{Ke^2}{2r^3}...
3
votes
2answers
67 views

Restrictions on transitions in Spectroscopy

Just for the sake of an example, let's assume a transition from one energy state to a higher energy state in atomic absorption spectrum If the energy difference between the ground state and first ...
3
votes
1answer
45 views

Electronic configuration of the actinides

I was reading about actinides and I need some help in understanding this paragraph from Concise Inorganic Chemistry by JD Lee - The electronic structures of the actinides do not follow the simple ...
3
votes
0answers
25 views

Are Slater’s rule and lanthanide contraction contradictory?

According to most textbook and the Wikipedia page of lanthanide contraction, the phenomenon is due to poor shielding of nuclear charge by 4f electrons. However, the σ value of 4f electrons to 6s is 1....
3
votes
0answers
497 views

Don't understand why Rutherford was shocked by results of gold foil experiment

The way Rutherford's classic gold foil experiment has been presented (including by Rutherford himself) doesn't make sense to me. As many of you know, Rutherford famously described himself as being ...
2
votes
1answer
84 views

Difference between probability and probability density of finding a particle in space

What is the difference between probability and probability density of finding a particle in space? I am at basics of the wave function and this thing confused me. Probability = $[\psi(x, y,z)]^2(\...
2
votes
2answers
151 views

Why did J.J. Thomson observe protons in his cathode ray experiment?

In this MIT lecture, at 7:22, the professor says that when J.J. Thomson added a positively charged plate on one side of the cathode ray and a negatively charged plate on the other side, he observed a ...
2
votes
1answer
39 views

Identifying orbital given electron probability density plot

Being a high-school student, I only have a qualitative understanding of the wave mechanical model of atom. Below are my inferences regarding the plot shown in the above picture: The concerned ...
2
votes
1answer
56 views

What facts are being used in this atomic structure question?

I wish to understand how to solve this atomic structure question: For the ground state, the electron in the H-atom has an angular momentum = $\hslash$ , according to the simple Bohr model. ...
1
vote
1answer
29 views

What is the unit of the Rydberg Constant? [duplicate]

In the image, the Rydberg constant seems to have two units. How is that possible?
1
vote
1answer
208 views

Strong or weak force between protons and neutrons?

I had learned that what keeps the protons and neutrons bound is the strong force and the weak force has to do with radioactive decay. but today I read an article from Science Daily that contradicts ...
1
vote
1answer
39 views

Why potential energy is neglected in this problem for calculating the energy difference between two stationary Bohr Orbits? [on hold]

Question An electron in a hydrogen like atom makes a transition from a state in which its de-Broglie wavelength is $\lambda_1$ to a state in which its de-Broglie wavelength is $\lambda_2$, then ...
1
vote
1answer
380 views

How does the screening effect work for orbital in the same shell?

Energy of an orbital in a single electron system depends solely on n, while energy of orbital in multi electron system depends on n and l, why is that? I understand that the screening effect is at ...
1
vote
0answers
30 views

Doubt in a question related to electronic transitions in Bohr's orbits

Question In Bohr series of lines of hydrogen spectrum, the third line from the red end corresponds to which one of the following inner-orbit jumps of the electron for Bohr orbits in an atom of ...
1
vote
0answers
31 views

How did Thomson calculate the momentum of electron when he didn't know the mass of electron?

"This was proven in 1903 by J. J. Thomson who calculated that the momentum of the electrons hitting the paddle wheel would only be sufficient to turn the wheel one revolution per minute." This is a ...
1
vote
0answers
31 views

What will happen if electron as a wave undergo destructive interference while travelling in its Orbit?

Today I came across a justification of Bohr's angular momentum quantization using the De- Broglie's hypothesis. The justification said that since the electrons are having wave nature also then while ...
1
vote
0answers
32 views

How did Planck reach the conclusion that energy comes in packets based on black body curves? [closed]

I understand that if wavelength continues to decrease energy emitted by an atom would get to infinite, but how does the max wavelength at a particular temperature translate to discrete energy packets. ...
1
vote
0answers
56 views

How can the potential energy at the infinite energy level in an atom be zero?

I have recently learnt about atomic structure and the Bohr model of the atom and have observed a discrepancy between it and my previous knowledge based on physics. For simplicity, assume the atom is ...
1
vote
0answers
24 views

Strongest overlap among s–s, p–p, s–p [duplicate]

So, I was wondering, when overlap of orbitals takes place, among s–s, s–p, p–p which type of overlapping is stronger? Because in s–s more volume is being used in overlap, but the electron density is ...
1
vote
1answer
47 views

Does one atom of an element show the properties of a bulk of that element? [duplicate]

For example, does one atom of gold have a golden color?
1
vote
0answers
32 views

Constructing two body Hamiltonian for Helium atom in hydrogen slater orbitals single particle basis [duplicate]

I am trying to construct a two body states to calculate the matrix elements of electronic Hamiltonian of Helium atom. $$H=-\frac{1}{2}\nabla^{2}_{1}-\frac{1}{2}\nabla^{2}_{2}-\frac{2}{\vec{r}_{1}}-\...
1
vote
0answers
375 views

Why are 4s electrons removed before 3d electrons? [duplicate]

According to Aufbau's Principle energy of 3d orbital is greater than 4s orbital, so which filling 4s if filled beforehand 3d. Whereas while removing electrons 4s electrons are removed first. Why? I ...
1
vote
0answers
132 views

Rutherford's alpha particle scattering experiment for sheets made of different metals [closed]

The correct order of increasing number of alpha particles passing undeflected through the foils of Au, Ag, Cu and Al of 1000 atoms thickness each in an alpha scattering experiment of Rutherford would ...
1
vote
0answers
47 views

Probabilities of Electrons in Orbitals [duplicate]

I've heard both of the following: An orbital is a region where there's a 90% probability of finding an electron An orbital is a region where an electron spends 90% of its time Are these essentially ...
1
vote
0answers
142 views

Quantum Mechanical Model of An Atom, Shells, Subshells [duplicate]

I've just been introduced to the quantum Mechanical Model of an Atom, so please bear with me on this one. Are Subshells and shell physical things, like do they really exist, or is it a concept only to ...
1
vote
0answers
44 views

How did the atomic number and atomic mass of elements discovered? [closed]

Elements are small for our naked eyes.so,how did the discovery of its atomic number and mass number took place?
1
vote
0answers
57 views

Why do objects gain electrons? [duplicate]

I have read that objects gain electrons to become negatively charged and also that they lose electrons to become positively charged. I have also read that same charges repel each other and non-same ...
0
votes
1answer
287 views

How are the molar mass and molecular mass of any compound numerically the same?

This observation is really annoying me, and the internet isn't providing me with any solid answers. Either their definitions of molar mass completely differ, or they don't stick to their own ...
0
votes
3answers
153 views

What are the possible magnetic quantum numbers of silver? [closed]

What are all the possible quantum numbers ml and ms of the electrons in the outermost s orbital of silver? I'm new to this concept. Can anyone walk me through this?
0
votes
1answer
84 views

Confusion about electron arrangement in elements

My textbook says, "The first shell can hold only 2 electrons. The second and subsequent shells can hold 8 electrons to give a stable noble gas arrangement." Can someone explain me if it is MAXIMUM 8 ...
0
votes
1answer
219 views

Finding region of electromagnetic spectrum with wavenumber

A line with wave number $\pu{1.028\times10^{-2} nm^{-1}}$ is emitted in the spectrum of atomic hydrogen. In what region of the electromagnetic spectrum does this line occur? Do we find this by ...
0
votes
1answer
71 views

Quantization and Bohr's model

According to quantization it's said that emitted or absorbed energy is quantized. Then, when it's said in bohr's model an electron changes its orbit (Let's say it goes to a higher energy shell from $...
0
votes
1answer
76 views

Radial Probability Distribution Curve versus ψ² versus r curve for 1s orbitals

My question is basic, but I have already referred to a couple of books. This is an excerpt from Linus Pauling's book: the most probable distance of the electron from the nucleus, which is the ...
0
votes
1answer
38 views

Deducing the shell when transition occurs such that two photons are discharged

Find $n$ (quantum number) corresponding to the excited state of $\ce{He+}$ ion if on transition to ground state the ion emits two photons in succession with wavelengths $\pu{108.5 nm}$ and $\pu{30.4 ...
0
votes
1answer
65 views

How are ions formed? [closed]

I know that $\ce{H2O}$ is neutral. So how does adding one more hydrogen atom to it make it positive ion ($\ce{H3O+}$)?
0
votes
0answers
10 views

He+ electronegativity

He+ can create multiple chemical substances bonded with chemical elements . Which value should it have? Would it be more electronegative than Oxygen ? Why do we give only neutral atoms ...