I'm not sure what happens when you add nacl, but kscn and hcl reacts to from an intensely red color in the presence of iron.
When KSCN, water (H2O), and hydrochloric acid (HCl) are mixed, the KSCN can react with HCl to form thiocyanic acid (HSCN). This reaction will release hydrogen cyanide gas (HCN), which is a toxic gas. Therefore, caution should be taken when working with these chemicals to prevent exposure to the toxic gas.
The reaction between potassium thiocyanate and ferric chloride forms a blood-red complex called ferric thiocyanate. This complex is formed due to the reaction between the thiocyanate ions from potassium thiocyanate and the iron(III) ions from ferric chloride. The balanced chemical equation for the reaction is: FeCl3 + 3 KSCN -> Fe(SCN)3 + 3 KCl.
FeCl3 + 6KSCN --> [Fe(SCN)6]-3 + 6K+ + 3Cl- This is a complex ion equation. K has a charge of +1 and Cl has a charge of -1 but since these form an aqueous solution, they are seperated. Put together, the equation cannot be balanced.
(K+ + SCN-)(aq) + (Ag+ + [NO3]-)(aq)---------------(K+ + [NO3]-)(aq) + AgSCN(s)
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.
With anything that contains Fe (3+) ions :-)
When you mix FeCl3 and KSCN, a blood red color forms due to the formation of Fe(SCN)2 complex. When AgNO3 is added to this solution, a white precipitate of AgSCN is formed, indicating the presence of thiocyanate ions in the solution.
Iron (III)
A blood-red color is obtained when potassium thiocyanate (KSCN) reagent is added to a ferric ion solution. This color change is due to the formation of a ferric thiocyanate complex.
If tap water turns a deep red color with a few drops of potassium thiocyanate (KSCN), it indicates the presence of iron(III) cations (Fe3+).
potassium thiocyanate
The mixing of 0.1 M FeCl3 and 0.1 N KSCN to form the blood-red complex FeSCN2+ is a chemical change because new substances with different chemical properties are formed due to a chemical reaction occurring between the Fe3+ ions and the SCN- ions.
When KSCN, water (H2O), and hydrochloric acid (HCl) are mixed, the KSCN can react with HCl to form thiocyanic acid (HSCN). This reaction will release hydrogen cyanide gas (HCN), which is a toxic gas. Therefore, caution should be taken when working with these chemicals to prevent exposure to the toxic gas.
Yes
Yes, KSCN can decompose into potassium sulfocyanate, sulfur dioxide, and nitrogen oxides when heated.
The name of the ionic compound KSCN is potassium thiocyanate.
Na2CO3 is added to prevent oxidation of cu+ ions which are repeatedly formed by reaction of Cu++ and I-.So, to prevent oxidation co2 is used in retarding reaction