Questions tagged [ions]
200 questions
31
votes
5 answers
Why are atoms electrically neutral?
I get the grade-school explanation that "the number of electrons equals the number of protons", but the electric field drops off with distance. If the protons are concentrated in the nucleus and the electrons are nebulously around the atom in…
19
votes
4 answers
Does Fire Conduct Electricity? Why?
Recently, I have stumbled upon a YouTube video by Veritasium describing the conductivity of fire. My question is: how exactly does fire conduct electricity? I am a high school student; therefore appropriate language is expected.…
PotatoIn
- 317
14
votes
2 answers
How can a salt solution conduct electrical current?
How does a sodium chloride solution conduct electricity?
I know that sodium chloride dissociates into sodium and chloride ions in water, so when a voltage is applied, those ions can move. However, if I have two poles of metal placed in a beaker and…
user209347
- 657
13
votes
1 answer
Can a discrete dynode mass spec detector get "tired?"
In an electron multiplier (discrete dynode detector), one electron triggers the release of more electrons in a cascade.
Is it possible that a "large" number of electrons hitting the detector can temporarily (course of hours) reduce the number of…
ZachB
- 231
12
votes
1 answer
Chemistry of electrical conductivity of pure water
I understand the electrical conductivity of pure water is very low, but not zero, and is due to the slight number of H+ and OH- ions naturally present. I understand that they will move under the influence of a potential difference and be the charge…
Paul R.
- 279
7
votes
1 answer
Can a salt water solution conduct electricity forever?
We know that very pure water does not conduct electricity, but salt water is a decent conductor. This is commonly explained by saying that "the ions carry the current through the solution", an explanation that does not really make sense because it…
DanHickstein
- 596
7
votes
5 answers
If lightning is caused by ionisation of air, why does it only last briefly?
I'm comparing lightning and fire - both are related to ionisation of air but lightning happens so fast in a blink of an eye while fire goes on until it runs out of fuel. My question is: despite being plasma just like a fire, why does lightning only…
user6760
- 13,214
6
votes
2 answers
Why aren't positive ions emitted at the same rate as electrons via thermionic emission?
The Effective Work Functions of the Elements are very similar for removing an electron or a positive ion, e.g. about 4.5 eV for Tungsten.
If their work functions are similar, why aren't positive ions emitted via thermionic emission at a similar rate…
David Bailey
- 13,658
6
votes
2 answers
Is NaCl vapour plasma?
Yesterday I asked a question at Chemistry SE, which is if the molten NaCl molecules have enough energy to break into free moving ions, won't be the Na Cl vapor contain free moving ions? So, I've got this answer telling me that that's what we call…
6
votes
2 answers
Why does the electrical conductivity of salt water increase with increase in temperature?
Is it due to the mobile ions that vibrate with higher energy that increases their conductance? It is noteworthy that the electrical conductivity in metals decreases as the temperature is increased but, why is it different from metals and…
Akarsh Ghale
- 83
6
votes
1 answer
Electricity is the movement of electrons or ions?
Electricity is the movement of electrons from one atom to another or the movement of charged negative particles (ions)?
Bhavesh
- 1,923
6
votes
3 answers
If an atom is fully ionized by removing all electrons, is it still an atom?
This is a question about terminology. To me, it's clear that the nucleus of an atom is still an atom. But a comment by Willie Wong at Is nature symmetric between particles and antiparticles? raises this question. Similarly, arguments go either way…
Carl Brannen
- 13,059
5
votes
1 answer
Can a homogeneous chemical solution really not be split by centrifuge?
Assuming I have a homogeneous solution such as salt in water. My intuition tells me that gravity or centrifugal forces would affect sodium ions more than water molecules. Theoretically, if I could centrifuge salt water fast enough for the pulling…
tobu
- 51
5
votes
3 answers
How come the number of wandering electrons is same as the number of the positive ions?
My book mentions the following:
Cause of resistance : When an ion of a metal is formed , its atoms lose electrons from its outer orbit . A metal ( or conductor ) has a large number of wandering electrons and an equal number of fixed positive ions .…
5
votes
1 answer
Can hydrogen have 3 electrons?
Can i in any way force a hydrogen atom to have three electrons? Two electrons in first shell and one in the second?
Hark
- 359