No. because it contains water of crystallization so it can absorb or release water..
In iodometry sodium thiosulphate is used because it is standardized by potassium dichromate and it is the best and relaible way to standardized sodium thiosulphate using iodometric titration. Infact sodium thiosulphate is also standardized by iodimetry. The difference between both of them is only of iodine. In iodometry iodine gas is liberated that will further react with sodium thiosulphate but in iodimetry standard solution of iodine is used.
To ensure the stability of the solution
why sodium thiosulfate to be prepared in hot water only
use the equation that is standard: 1000 ml 1 M solution= (MOLECULAR WEIGHT) X ml 0.05 M solution = ((MOLECULAR WEIGHT)*X*0.05)/1000
Because it used to be called Sodium hyposulphite.
In iodometry sodium thiosulphate is used because it is standardized by potassium dichromate and it is the best and relaible way to standardized sodium thiosulphate using iodometric titration. Infact sodium thiosulphate is also standardized by iodimetry. The difference between both of them is only of iodine. In iodometry iodine gas is liberated that will further react with sodium thiosulphate but in iodimetry standard solution of iodine is used.
it is a secondary solution because it can change its concentration by absorbing moisture....
Sodium thiosulphate solution (5-25 %)
To ensure the stability of the solution
Sodium thiosulphate solution (5-25 %)
· In analytical chemistry, sodium thiosulphate is used for the determination of the strength of a given solution of iodine. · Sodium thiosulphate is preferred in iodometric analysis due to the fact that sodium thiosulphate is oxidized by iodine. It is also used to determine the strength of many oxidizing agents.
Sodium chloride is a crystalline solid but can be dissolved in water to form a solution.
why sodium thiosulfate to be prepared in hot water only
to acidify the solution
Titrate each solution separately with solution of known concentration of sodium thiosulphate. The titre value will give the amount of thiosulphate reacted with iodine, hence you can find concentration of iodine.
reaction takes place faster than of a solution that is less concentrated
sodium thiosulphate