ia HELPP Sodium Thiosulfate and HCl rate of reaction?

[abelkoontz]

I'm determining the activation energy of the reaction between sodium thiosulfate and HCl. 

I just wanted to check if i was doing the experiment right

I have 3g of Sodium thiosulfate solid and add it to 10ml - 20ml of HCl

I'm changing the concentration of HCl but online i found that people changed the concentration of the sodium thiosulfate. I dont have sodium thiosulfate in liquid form what do it do?? 

[Msj Chem]

It is possible to make a solution of sodium thiosulfate. 

[kw0573]

Sodium thiosulfate is highly dissolvable in water. You can add the sodium thiosulfate directly into the HCl solution and the salt will become aqueous. So you can convert mass of the salt to mol and calculate molar concentration (molarity). When diluting the acid remember to add the acid to water, not adding water to acid. To only change concentration of the salt you can add different masses of it to the same volume of HCl solution.