0
Why amnomiun thiocyanate is added in the titration of sodium thiosulphate with copper?
SaiaraSamira
Want this question answered?
Be notified when an answer is posted
Add your answer:
Earn +20 pts
Why potassium thiocyanate is added in the titration of sodium thiosulphate with copper?
On addition of the KI to your copper (II) solution, you formed Copper (I) iodine solid and produced the tri-iodide ion. It is the tri-iodide ion that you are titrating with the sodium thiosulfate. The tri-iodine ion is what itercalates into the starch molecules to form the dark blue color you are using as an end point in the titration. Some the the tri-iodide ion formed will adsorb to the surface of the solid copper (I) iodine formed. This must be desorbed for a complete titration. The addition of the potassium thiocyanate, displaces the adsorbed tri-iodine ion, and liberates it for titration.
What is the usage of KCNS in a iodometric titration?
Some of the metal ion that is estimated (especially Cu2+) may get trapped within starch indicator. When KCNS is added, copper thiocyanate or Cu(CNS)2 complex is formed which then reacts with the KI added, giving correct results.
In estimation of copper and nickel why we are using volumetric for copper and gravimetric for nickel seperately?
It is simply because they could not be found together!! copper can be estimated by treating with potassium iodide and iodine will be liberated in the reaction which is titrated against sodium thiosulphate during the reaction we will add sulphuric acid to prevent the hydrolysis of copper sulphate and we follow by, adding ammonia to neutralize sulphuric as it may hinder the reation between iodide and copper!! now again we will add acetic acid to neutralize ammonia.. and the indicator is added at the last because it will get absorbed with the iodine!! now atlast we add ammonium, thiocyanate to prevent the excess of iodine getting added to copper iodide. end point is disappearance of blue color.
Explain about Condutometric titration's of copper sulphate with sodium hydroxide?
how the end point is determined
What is the difference between anhydrous sodium thiosulphate and sodium thiosulphate?
None. Anhydrous simply means ..... (not in solution). The opposite is aqueous (in solution).Added:..... crystalised without hydrate in the solid crystals.mono-hydrate means it is crystallised with 1 (one) molecule H2O per molecule salt.CuSO4.5H2O means : penta-hydrate of copper sulfate
Why potassium thiocyanate is added in the titration of sodium thiosulphate with copper?
On addition of the KI to your copper (II) solution, you formed Copper (I) iodine solid and produced the tri-iodide ion. It is the tri-iodide ion that you are titrating with the sodium thiosulfate. The tri-iodine ion is what itercalates into the starch molecules to form the dark blue color you are using as an end point in the titration. Some the the tri-iodide ion formed will adsorb to the surface of the solid copper (I) iodine formed. This must be desorbed for a complete titration. The addition of the potassium thiocyanate, displaces the adsorbed tri-iodine ion, and liberates it for titration.
What is produced when Copper nitrate and potassium thiocyanate react?
copper (thiocyanate)2 and potassium nitrate
Why is KSCN used in iodometry of copper?
On addition of the KI to your copper (II) solution, you formed Copper (I) iodine solid and produced the tri-iodide ion. It is the tri-iodide ion that you are titrating with the sodium thiosulfate. The tri-iodine ion is what itercalates into the starch molecules to form the dark blue color you are using as an end point in the titration. Some the the tri-iodide ion formed will adsorb to the surface of the solid copper (I) iodine formed. This must be desorbed for a complete titration. The addition of the potassium thiocyanate, displaces the adsorbed tri-iodine ion, and liberates it for titration.
What is the formula for copper ii thiocyanate?
Cu2CuN2S2
What is the usage of KCNS in a iodometric titration?
Some of the metal ion that is estimated (especially Cu2+) may get trapped within starch indicator. When KCNS is added, copper thiocyanate or Cu(CNS)2 complex is formed which then reacts with the KI added, giving correct results.
Why potassium thiocyanate is added in redox iodometric titration of copper sulphate?
Cu2I2 is precipitates in light pink colour due to adsorption of I2 and the precipitate releases I2 very slowly. Therefore very small amount of potassium thiocyanate is added towards the end point which helps to displace the adsorbed I2 quickly by combining with Cu2I2 to form CuSCN which has less tendency to adsorb I2.
In estimation of copper and nickel why we are using volumetric for copper and gravimetric for nickel seperately?
It is simply because they could not be found together!! copper can be estimated by treating with potassium iodide and iodine will be liberated in the reaction which is titrated against sodium thiosulphate during the reaction we will add sulphuric acid to prevent the hydrolysis of copper sulphate and we follow by, adding ammonia to neutralize sulphuric as it may hinder the reation between iodide and copper!! now again we will add acetic acid to neutralize ammonia.. and the indicator is added at the last because it will get absorbed with the iodine!! now atlast we add ammonium, thiocyanate to prevent the excess of iodine getting added to copper iodide. end point is disappearance of blue color.
Explain about Condutometric titration's of copper sulphate with sodium hydroxide?
how the end point is determined
What is the difference between anhydrous sodium thiosulphate and sodium thiosulphate?
None. Anhydrous simply means ..... (not in solution). The opposite is aqueous (in solution).Added:..... crystalised without hydrate in the solid crystals.mono-hydrate means it is crystallised with 1 (one) molecule H2O per molecule salt.CuSO4.5H2O means : penta-hydrate of copper sulfate
Easy Analytical techniques zinc sulphate Ferrous sulphate Copper sulphate through titration method?
analysis purpase
What is the function of NH4CNS in estimation of the amount of copper present in a supplied solution by iodometric method?
The end-point of the titration is more sharper if NH4CNS exist in the solution;
Can you please give examples of chemistry investigatory project I need it for my project in chemistry?
Prepare a sample of tetraamine copper (II) sulfate. (Despite the name it's very easy to produce). Analyze the percent by mass of copper ion, sulfate and ammonia in your compound. Very easy and impressive experiment if you have access to some standard lab equipment. Copper is analyzed by titration, sulfate is precipitated out with barium (II) chloride and measured using simple stoichiometry, ammonia is analyzed by back titration. Feel free to message me if you have any questions.
