single anion replacement

[stormyweathers]

I have a great interest in chemistry, however i have only taken a single class in it [more to come when school starts again]. In class we discussed single and double replacement reactions. But, as far as the single replacements go, we only discussed replacing the cation.

Do single replacements work the same for anions?

if so, are they called something different?

is there an activity series for anions too?

[LGM]

Do you mean like 2 NaCl+F2 --> 2 NaF + Cl2? If so, yes.

 

The scale for how reactive the anions are is called electronegativity, you can look up a chart of the electronegativity of ions.

[stormyweathers]

perfect, yea thats exactly what i was talking about.

is it still called a single replacement?

[Steps]

I think its called a Single Displacement Reaction.

[Mumbles]

These kind of reactions arn't as common as the one using metals and the activity series. While the demonstrations would be fun, they're in general more dangerous. Generally they're done with a double replacement reaction, utilizing solubilities to drive the reaction toward your desired compound. For example:

 

NaCl + Pb(NO3)2 ---> PbCl2 + 2 NaNO3

 

The sodium essentially is inert in the reaction, and is only there as a chloride source, sometimes called a spectator ion. I seem to remember a different name for this kind of reaction. Though I've heard it called a metathesis, I tend to think of organic chemistry and Grubbs when I heard it in respect to a reaction.

[TYRONEEZEKIEL]

Is this the same concept to KNO3 + NH4ClO4 -> NH4NO3 + KClO4?

[stormyweathers]

thats the same reaction mumbles mentioned.

but im not sure if that reaction would even take place, because both products would be soluble in water.

but i was asking about a reatction like the fluorine one given at the begining of the thread.

 

The main purpose of the question was because i was looking for a simple way to convert my carbonate salts to chlorides on a small scale.

 

Would bubbling chlorine gas through the salts react in the desired wayy?

[Swede]

There is also this classic replacement, although not one of the anion:

 

Cu metal + silver nitrate --> Ag metal + Copper Nitrate

 

My friend and I converted several gallons of silver nitrate into a pile of black silver powder, which was easily melted into a pretty hefty nugget of silver. The professor wondered how in the world all the stock silver nitrate got so buggered.

 

I was quite evil in my youth. But I maintain, the hundred grams of dinitrotoluene (a dangerous toxic solid) that was found in a cabinet by the same teacher months later, I had nothing to do with.

Edited July 8, 2009 by Swede

[Mumbles]

Potassium Perchlorate is only sparingly soluble, so yes, that reaction happens quite easily.

 

Converting carbonates to chlorides is very easy, and no need to the horrible chlorine gas. It would probably work, but be very slow, and very dangerous. All you'd need to do is add the salts to HCl. You know, the baking soda, and vinegar thing? Same concept. Acid-Base.

[stormyweathers]

awesome, i need some chloride salts for a colored lantern demo im doing for some friends.

two more questions though:

would muraitic acid work? given the impurities?

 

and heres my plan:

 

using 50g of each chloride salt per gallon of methanol.

 

could i use an adjusted concentration of carbonate salt, and add a chlorine donor to the fuel mixture?

[TYRONEEZEKIEL]

Muriatic acid IS HCl. and it works fine! Its not impure, its just dilute with water. Pure HCl will evaporate very very fast and is not practical for use.

[Mumbles]

Pure HCl is a gas. It's not even really acidic in it's anhydrous state as there are no protons dissociated, though don't take that to mean non-corrosive or not dangerous. Muriatic acid is actually pretty concentrated solution. 31.45% usually, where as fully concentrated is around 38%, and that only is stable at freezing temperatures, or it will lose gas.

 

The useful carbonates are not soluble in methanol. I'd be careful with adding chlorine donors, or acid to methanol. I've experimented with it in the past. It's easier than you'd think to generate phosgene.

[stormyweathers]

wow, thats usefull information.

i had assumed that muratic acid would be a mixture of other chemicals too.

 

and i guess that low sounding concentration would have quite a high molarity based on the low molecular weight of HCl