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Ionic equation for reaction between chlorine and sodium thiosulphate

Does anyone know the ionic equation for the reaction between chlorine and sodium thiosulphate and how to work it out? I kind of get the idea but end up confusing myself!
Thanks
I will take a guess

2S2O3 + Cl2 ---> 2Cl + S4O6

May want to verify that : )
put the charges in and it looks fine to me.
Reply 3
thanks guys, just looked at the question again it says -
Sodium thiosulphate reacts with chlorine to produce sulphate ions, chloride ions and hydrogen ions. Write a balanced ionic equation for the reaction between chlorine and sodium thiosulphate.

just wonderin where the hydrogen ions fit into it? lol
Unparseable latex formula:

$[br]S_2O^{2-}_3+4Cl_2+5H_2O \longrightarrow 10H^++2SO^{2-}_4+8Cl^-[br]



you can get it from the half equations of the oxidation of thiosulphate to sulphate and reduction of chlorine to chloride

This reaction would occour rather than the other one I guess is because Chlorine is a stronger oxidising agent than Iodine so can oxidise the thiosulphate :smile:
Unparseable latex formula:

$[br]S_2O^{2-}_3 + 5H_2O \longrightarrow 10H^++2SO^{2-}_4+8e^-



Unparseable latex formula:

$[br]Cl_2 + 2e^- \longrightarrow 2Cl^-[br]

Reply 5
Can some one confirm this reaction as the chemical reaction is not getting balanced like ionic reaction

Original post by thelostchild
Unparseable latex formula:

$[br]S_2O^{2-}_3+4Cl_2+5H_2O \longrightarrow 10H^++2SO^{2-}_4+8Cl^-[br]



you can get it from the half equations of the oxidation of thiosulphate to sulphate and reduction of chlorine to chloride

This reaction would occour rather than the other one I guess is because Chlorine is a stronger oxidising agent than Iodine so can oxidise the thiosulphate :smile:
Unparseable latex formula:

$[br]S_2O^{2-}_3 + 5H_2O \longrightarrow 10H^++2SO^{2-}_4+8e^-



Unparseable latex formula:

$[br]Cl_2 + 2e^- \longrightarrow 2Cl^-[br]

Reply 6
can some one confirm the products are possible as the reaction is not getting balanced like ionic reaction
Reply 7
Original post by JANOSA
Can some one confirm this reaction as the chemical reaction is not getting balanced like ionic reaction


I find it difficult to balance the equation below:
Na2S2O3 + Cl2 + H2O Na2SO4 + NaCl + H2

Can some one help me
Reply 8
I find it difficult to balance the equation below:
Na2S2O3 + Cl2 + H2O Na2SO4 + NaCl + H2

Can some one help me
Correct balanced chemical equation for this reaction is 2Cl2 + 2H2O + 2Na2S2O3 ------->; 4NaCl + H2S4O6 + 2OH-ions
(edited 5 years ago)
Original post by Sakshi Arora
Correct balanced chemical equation for this reaction is 2Cl2 2H2O 2Na2S2O3 -------> 4NaCl H2S4O6 2OH-ions


The OP made this post 9 years ago!

This cannot be correct - you have two negative charges on the RHS mysteriously appearing and none on the LHS

Here's the correct equation:

Half-equation 1: 2S2O32- --> S4O62- + 2e
Half-equation 2: Cl2 + 2e --> 2Cl-
-------------------------------------------------------------- add together
2S2O32- + Cl2 --> S4O62- + 2Cl-

If you're bothered about putting in the balancing ions, use sodium.

2Na2S2O3 + Cl2 --> Na2S4O6 + 2NaCl
(edited 5 years ago)
Correct balanced chemical equation for this reaction is 2Cl2 2H2O 2Na2S2O3 -------> 4NaCl H2S4O6 2OH-ions
Since this post has been reborn, some clarifications are warranted for those reading later.

Reactions of sodium thiosulfate and chlorine are pH dependent. With reactions at pH's less than 8.9 and greater than 6, the dominant aqueous chlorine species is ClO- and there are the following two possible reactions:

The dominant reaction: S2O32- + 4ClO- + H2O ---> 4Cl- + 2H+ 2SO42-

The minor reaction: 2S2O2- + ClO- +H20 ---> Cl- + 2HO- + S4O62-

There are several other possible reactions at lower pH's. Note in the dominant reaction that acidic hydrogen is generated and in the minor reaction basic hydroxide is generated. More than likely the minor reaction starts taking more precedence as the solution approaches higher pH's. For most neutralizations around pH 7, I use 4 mole Cl(-) per 1 mole S2O3(2-) from the dominant reaction. You can always just use 2:1 and spend more money. In practicality, one may have to add a little thiosulfate using 4:1 since there are two viable reactions that actually occur. In other words, as the neutralization proceeds through the primary reaction, the minor reaction starts coming into play. This is governed theoretically by the activity of the reagents and products.
(edited 5 years ago)
Original post by countrychem
Since this post has been reborn, it does need some clarifications for those coming upon it later.

Reactions of sodium thiosulfate and chlorine are pH dependent. With reactions at pH's less than 8.9 and greater than 6, the dominant aqueous chlorine species is ClO- and there are the following two possible reactions:

The dominant reaction: S2O32- + 4ClO- + H2O --> 4Cl- + 2H+ + 2SO42-
The minor reaction: 2S2O2- + + ClO- + H2O --> Cl- + 2HO- + S4O62-

There are several other possible reactions at lower pH's. Note in the dominant reaction that acidic hydrogen is generated and in the minor reaction basic hydroxide is generated. More than likely the minor reaction starts taking more precedence as the solution approaches higher pH's. For most neutralizations around pH 7, I use 4 moles Cl(-) per 1 mole S2O3(2-) from the dominant reaction. You can always just use 2:1 and spend more money. In practicality, one may have to add a little thiosulfate using 1:4 since there are two viable reactions that actually occur. In other words, as the neutralization proceeds through the primary reaction, the minor reaction starts coming into play. This is governed theoretically by the activity of the reagents and products.

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