Home
Class 12
CHEMISTRY
H(2)S in the presence of HCl precipitate...

`H_(2)S` in the presence of `HCl` precipitates `II` group but not `IV` group because:

A

`HCl` activates `H_(2)S`

B

`HCl` increase concentration of `Cl^(-)`

C

`HCl` decreases concentration of `S^(2-)`

D

`HCl` lowers the solubility of `H_(2)S` in solution.

Text Solution

Verified by Experts

The correct Answer is:
C
`H_(2)S hArr2H^(+)+S^(2-),HClhArrH_(2)^(+) +Cl^(-)`
Due to common ion effect, the ionisation of `H_(2)S` is suppressed and thus low concentration of `S^(2-)` ions is obtained This much of `S^(2-)` ions concentration is enough to precipitate only `II^(nd)` group cations (because of the low `K_(SP)` of `II^(nd)` group sulphides)
Promotional Banner

Similar Questions

Explore conceptually related problems

Mg is not precipitated in V group because:

Mg is not precipitate in group V because

In the presence of dilute HCl, H_(2)S results in the precipitation of group II cations but not group IV cations during qualitative analysis. It is due to :

In equalitative analysis, cations of graph II as well as group IV both are precipitated in the form of sulphides. Due to low value of K_(sp) of group II sulphides, group reagent is H_(2)S in the presence of dil. HC1 , and due to high value of K_(sp) of group IV sulphides, group reagent is H_(2)S in the presence of NH_(4)OH and NH_(4)C1 . In a solution containing 0.1M each of Sn^(2+), Cd^(2+) , and Ni^(2+) ions, H_(2)S gas is passed. K_(sp) of SnS = 8 xx 10^(-29), K_(sp) of CdS = 15 10^(-28), K_(sp) of NiS - 3 xx 10^(-21), K_(1) of H_(2)S = 1 xx 10^(-7), K_(2) of H_(2)S = 1 xx 10^(-14) At what value of pH, NiS will start to precipitate?

In equalitative analysis, cations of graph II as well as group IV both are precipitated in the form of sulphides. Due to low value of K_(sp) of group II sulphides, group reagent is H_(2)S in the presence of dil. HC1 , and due to high value of K_(sp) of group IV sulphides, group reagent is H_(2)S in the presence of NH_(4)OH and NH_(4)C1 . In a solution containing 0.1M each of Sn^(2+), Cd^(2+) , and Ni^(2+) ions, H_(2)S gas is passed. K_(sp) of SnS = 8 xx 10^(-29), K_(sp) of CdS = 15 10^(-28), K_(sp) of NiS - 3 xx 10^(-21), K_(1) of H_(2)S = 1 xx 10^(-7), K_(2) of H_(2)S = 1 xx 10^(-14) Which of the following sulphides is more soluble in pure water?

In equalitative analysis, cations of graph II as well as group IV both are precipitated in the form of sulphides. Due to low value of K_(sp) of group II sulphides, group reagent is H_(2)S in the presence of dil. HC1 , and due to high value of K_(sp) of group IV sulphides, group reagent is H_(2)S in the presence of NH_(4)OH and NH_(4)C1 . In a solution containing 0.1M each of Sn^(2+), Cd^(2+) , and Ni^(2+) ions, H_(2)S gas is passed. K_(sp) of SnS = 8 xx 10^(-29), K_(sp) of CdS = 15 10^(-28), K_(sp) of NiS - 3 xx 10^(-21), K_(1) of H_(2)S = 1 xx 10^(-7), K_(2) of H_(2)S = 1 xx 10^(-14) If H_(2)S is passed into the above mixture in the presence of HC1 , which ion will be precipitated first?

In equalitative analysis, cations of graph II as well as group IV both are precipitated in the form of sulphides. Due to low value of K_(sp) of group II sulphides, group reagent is H_(2)S in the presence of dil. HC1 , and due to high value of K_(sp) of group IV sulphides, group reagent is H_(2)S in the presence of NH_(4)OH and NH_(4)C1 . In a solution containing 0.1M each of Sn^(2+), Cd^(2+) , and Ni^(2+) ions, H_(2)S gas is passed. K_(sp) of SnS = 8 xx 10^(-29), K_(sp) of CdS = 10^(-28), K_(sp) of NiS - 3 xx 10^(-21) K_(1) of H_(2)S = 1 xx 10^(-7), K_(2) of H_(2)S = 1 xx 10^(-14) If 0.1M HC1 is mixed in the solution containing only 0.1 M Cd^(2+) ions and saturated with H_(2)S , then [Cd^(2+)] remaining in the solution after CdS stopes to precipitate is:

Why Na_(2)S cannot be used in place of H_(2)S (in presence of HCl ) as a reagent for II^(nd) group cations ?

In salt solution when H_(2)S pass in presence of dil HCl , a orange color precipitate obtained.Radical & composition of precipitate will be

Hydrogen can be put in halogen group because: