All Questions
109
questions
37
votes
3
answers
47k
views
Why do atoms generally become smaller as one moves left to right across a period?
It seems to me that the addition of electrons and protons as you move across a period would cause an atom to become larger. However, I'm told it gets smaller. Why is this?
- 827
27
votes
1
answer
3k
views
While filling electrons, we follow Aufbau principle, but not while removing them. Why is this so?
I recently came across a question Why is the vanadium(3+) ion paramagnetic?, where the asker is wondering how $\ce{V^{3+}}$ is paramagnetic (he used Aufbau in reverse to remove the electrons), while ...
21
votes
5
answers
298k
views
What is SPDF configuration?
Recently in my chemistry classes, the teacher spoke about SPDF configuration and then said that we'll be taught about it in higher classes.
But I'm sorta curious to know that what is SPDF ...
- 979
17
votes
4
answers
3k
views
Why is the electron-nucleus attraction modelled with only electrostatic interactions?
While reading about the structure of an atom, I've encountered (even in some renowned books) the statement that electrons and nuclei are attracted due to electrostatic, or Coulombic, attractions.
...
- 297
16
votes
4
answers
5k
views
Why do electrons jump back after absorbing energy and moving to a higher energy level?
Electrons in a shell absorb energy and move to higher energy levels, but they release their energy and jump back to the shell they originally were in. Why do they jump back? Why can they not keep ...
- 189
14
votes
2
answers
2k
views
Why are dipoles "permanent/induced dipole permanent/induced dipole" and not just "permanent/induced dipole" once?
My teacher would always say "induced dipole induced dipole" and while it annoyed my slightly (as you were saying the same word twice) it didn't really bother me, ...
- 475
14
votes
1
answer
4k
views
Inter electronic repulsion in s and d orbitals
This was written in a lecture slide:
Two electrons present in the same d-orbital repel each other more strongly than do two electrons in the same s-orbital.
Why is there a difference in the amount ...
- 7,804
13
votes
2
answers
520
views
Do multielectron atoms have nodes?
For hydrogen, other than in the 1s state, the electron wavefunctions have radial and/or angular nodes where the electron probability density is zero.
In helium or further atoms with more than one ...
- 40.9k
9
votes
1
answer
723
views
Why does the same electron transition release photons of different frequencies for some elements?
Question: For elements in the same period with different numbers of valance electrons, why does the same electron transition release photons of different frequencies?
Example: For valance electrons ...
- 103
9
votes
1
answer
283
views
Fundamentals of Li-ion Functionality
I would like to have an in-depth understanding of Li-ion batteries functionality, at atomic level. Can anyone help me to understand it? I have included some known background to support my questions.
...
- 944
8
votes
2
answers
7k
views
Why do electrons need to be paired?
I’d read that it takes energy to place electrons in pairs, just less than it would take to place two electrons in different subshells. I get that. What I don’t get is, then, why would electrons want ...
- 1,529
8
votes
1
answer
12k
views
Anomalous Electronic Configuration of Thorium
The electronic configuration of thorium ($Z=90$) is $5\mathrm f^0 6\mathrm d^2 7\mathrm s^2$. But, according to the aufbau principle, the electrons should first enter the $\mathrm f$ subshell and not ...
- 89
7
votes
1
answer
3k
views
Can there exist any element with an 8th principal shell?
I am a high school student. While studying the atomic structure a question appeared to me. We know that an atom can have the highest limit of 7 Bohr energy shells or principal energy shells, ...
- 183
7
votes
1
answer
135
views
Confusion about the number of microstates for orbitals
I am very confused about the microstates for a specific orbital.
Let's suppose I have an electronic configuration
$$
\ce{[\dots] 2p^5}
$$
Considering the symmetry of the orbitals and the "...
- 79
6
votes
2
answers
4k
views
How can two electrons lie together in an orbital?
Two electron of opposite spin can lie in a single orbital.. But what about the electron-electron repulsion.
Okay! I got that the nuclear charge rather the large Z-effective overcome this repulsion by ...
- 749