Table of Contents
What is the role of HCl in Group Test for Group second?
The group reagent of II group is sulphide ion, S2- but HCl is added to induce common ion effect. The presence of H+ ions lower the dissociation of H2S and lesser S2- ions are formed. As a result only the cations of lower Ksp get precipitated.
Why do we add dil HCl before proceeding to Analyse cations of group II?
dilute HCl increasing the concentration of h + ions in the solution and hence suppresses the dissociation of H2S due to common Ion effect. As a result of which the sulphide ions concentration is sufficient only to exceeds the solubility product of the sulphides of Group II cations.
What is the difference between ionic product and solubility product?
The difference between ionic product and solubility product is that ionic product is the product of ions in either an unsaturated or saturated solution whereas solubility product is the product of ions in saturated solutions.
Why is dilute H2SO4 preferred over dilute HCl during anions?
H2SO4 is preferred while testing acid radicals over dil. HCl? Ans. So the actual gas cannot be identified whereas with H2SO4, no such problem arises.
Why do we use cone HCl in preparing a paste of the salt for flame test?
Why do we use cone. HCl in preparing a paste of the salt for flame test? Ans. In order to convert metal salts into metal chlorides which are more volatile than other salts.
Why H2S is passed in presence of HCl?
When H2S is passed in presence of dil. HCl, the dissociation of H2S is weak due to common ion effect. So the sulfide concentration in the solution is very low which is sufficient to react with the cation of group 2 and falls out as HgS,PbS,Bi2S3,CuS,CdS,As2S3,Sb2S3,SnS.
What will easily precipitate when HCl is passed through H2S?
HCl and H2S . Co is the alkaline radical of IV group which is precipitated in the presence of H2S gas and is NH4OH .
What is a high KSP?
Ksp (Solubility product constant) is the equilibrium between a solid and its respective ions in a solution. The value of the constant identifies the degree of which the compound can dissociate in water. For example the higher the Ksp the more soluble the compound is.