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Old Nov 4th 2018, 11:04 PM   #1
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Anion and Cation

I am not a student of chemistry, and I am posting it here because I never got a response from "Chemistry help" forum.

my question is
1: What are anion solution and cation solution...can anyone give an example for it??
2: How can we prepare lanthanum fluoride (LaF).I mean what chemicals should be used to prepare LaF? if possible please write reactions for it.
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Old Nov 5th 2018, 02:34 AM   #2
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1. Consider a crystal of salt ..NaCl ... the sodium and chlorine atoms are locked in a tight lattice.... when dissolved in water the atoms separate and float around ... the Na atoms carry a +ve charge and are called cations ... the chlorine atoms carry a -ve charge and are anions .... the solution must contain both.

2. LaF ...Lanthanum is a soft metal ...Florine is a very reactive gas , just put them together and stand well back ... La + F = LaF
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Old Nov 5th 2018, 07:13 AM   #3
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Some elements have a strong affinity for electrons, while others have a very weak attachment.
(this is due to the physics of the quantum interactions of the electrons with the nucleus).
If a strongly attracting element is reacted with a weakly attracting element
then the weakly attracting element will loose an electron (sometimes more than one) to the strongly attracting element.
This leads to the atoms of one of the elements being positively charged (anions),
while the atoms of the other element become negatively charged (cations).
In a solid the positive and negative charges hold the elements together,
however in solution, the anions and cations are (relatively) free to move with respect to each other.
Indeed if an electrical current is passed through the solution, they can be made to separate.
Note that while we have concentrated our answers around elements (for simplicity)
the same arguments can be applied to some more complex compounds.

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Old Nov 5th 2018, 09:39 AM   #4
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Originally Posted by oz93666 View Post
1. Consider a crystal of salt ..NaCl ... the sodium and chlorine atoms are locked in a tight lattice.... when dissolved in water the atoms separate and float around ... the Na atoms carry a +ve charge and are called cations ... the chlorine atoms carry a -ve charge and are anions .... the solution must contain both.

2. LaF ...Lanthanum is a soft metal ...Florine is a very reactive gas, just put them together and stand well back ... La + F = LaF
Its means those solutions which have only positive charges in it will be called cation solutions and the other with a negative charge will be called anion solutions right? Is it possible to have a solution of one kind of charge i.e positive or negative?

Can we prepare LaF by using La(NO3)3 with any of fluoride solution?
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Old Nov 5th 2018, 09:46 AM   #5
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Originally Posted by Woody View Post
Some elements have a strong affinity for electrons, while others have a very weak attachment.
(this is due to the physics of the quantum interactions of the electrons with the nucleus).
If a strongly attracting element is reacted with a weakly attracting element
then the weakly attracting element will loose an electron (sometimes more than one) to the strongly attracting element.
This leads to the atoms of one of the elements being positively charged (anions),
while the atoms of the other element become negatively charged (cations).
In a solid the positive and negative charges hold the elements together,
however in solution, the anions and cations are (relatively) free to move with respect to each other.
Indeed if an electrical current is passed through the solution, they can be made to separate.
Note that while we have concentrated our answers around elements (for simplicity)
the same arguments can be applied to some more complex compounds.

All forums require volunteers (AKA show-offs) to respond to peoples posts
and (ideally) answer their questions.
The Chemistry Help Forum has not managed to attract sufficient such individuals to make it work.
So by passing current, the charges get separated and that's the way we get anion solution and cation solution?
its mean those solutions which have only positive charges are cation solutions and those with negative charges are anion solutions right?
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Old Nov 5th 2018, 10:01 AM   #6
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A solution must always have an (approximately) equal mix of anions and cations,
otherwise it will have an overall electrical charge.

I am not actually familiar with the use of the terminology for anion or cation solutions, however:

Some ionic compounds are, more reactive than others.
thus if you have a highly reactive cation with a sluggish anion then the cation will take the lead in any reactions,
so this could perhaps be called a cation solution.

Fluorine is a very highly reactive cation (much more reactive than NO3).
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Old Nov 5th 2018, 11:25 PM   #7
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Originally Posted by Woody View Post
A solution must always have an (approximately) equal mix of anions and cations,
otherwise, it will have an overall electrical charge.

I am not actually familiar with the use of the terminology for anion or cation solutions, however:

Some ionic compounds are, more reactive than others.
thus if you have a highly reactive cation with a sluggish anion then the cation will take the lead in any reactions,
so this could perhaps be called a cation solution.

Fluorine is a very highly reactive cation (much more reactive than NO3).
Thank you for your answers were helpful.
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