Which of the following cations cannot be separated by passing \(H_2S\) through their solutions to which \(NH_4OH\) has been added?

(a) \(Ca^{2+}\) and \(Ni^{2+}\)
(b) \(Mg^{2+}\) and \(Mn^{2+}~\)
(c) \(Ni^{2+}\) and \(Mn^{2+}\)
(d) \(Co^{2+}\) and \(Zn^{2+}\)

1. (a), (b), (d)
2. (c) and (d) 
3. (a), (b), (c)
4. None of the above
 
 

Subtopic:  Detection of Cations |
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Incorrect statements among the following are:
(a) Group I radicals are precipitated as chloride
(b) Group IV radicals are precipitated as sulphide
(c) Group V radicals are precipitated as hydroxide
(d) Group III radicals are precipitated as chloride
 
1. (a), (b) and (d)
2. (c) and (d) 
3. (a), (b) and (c)
4. (a), (b), (c) and (d)
Subtopic:  Detection of Cations |
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 \(Fe^{3+},Zn^{2+}\) and \(Cu^{2+}.\) cations  are present in a slightly acidic solution. The reagent that when added in excess to this solution would identify to separate \(Fe^{3+}\) in one step is: 
1. \(2M~HCl \)
2. \(6M~NH_3 \)
3. \(6M~NaOH \)
4. \(H_2S~\) gas 
Subtopic:  Detection of Cations |
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An aqueous solution of a substance gives a white precipitate on treatment with dilute hydrochloric acid, which dissolves on heating.cWhen hydrogen sulfide is passed through the hot acidic solution, a black precipitate is obtained.
The substance is a:
1. \(Hg^{2+}_2\) salt 
2. \(Cu^{2+}\) salt 
3. \(Ag^+\) salt 
4. \(Pb^{2+}\) salt 
Subtopic:  Detection of Cations |
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A solution when diluted with \(H_2O\) and boiled, gives a white precipitate. Upon addition of excess \(NH_2Cl/NH_4OH, \) the volume of precipitate decreases, leaving behind a white gelatinous precipitate. Identify the precipitate that dissolves in \(NH_4OH/NH_4Cl\)
1. \(Al(OH)_3\)
2. \(Z n(OH)_2\)
3. \(Ca(OH)_2\)
4. \(Mg(OH)_2\)
Subtopic:  Detection of Cations |
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An aqueous solution of metal ion M1 reacts separately with reagents Q and R in excess to give tetrahedral and square planar complexes, respectively. An aqueous solution of another metal ion M2 always forms tetrahedral complexes with these reagents. Aqueous solution of M2 on reaction with reagent S gives a white precipitate which dissolves
in excess of S. The reactions are summarized in the scheme given below.
M1, Q, and R, respectively, are:

1. \(Zn^{2+}, ~ KCN\) and \(HCl\)
2. \(Ni^{2+},~ HCl\) and \(KCN\)
3. \(Cd^{2+}, ~KCN\) and \(HCl\)
4. \(Co^{2+},~ HCl\) and \(KCN\)
 
Subtopic:  Detection of Cations |
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During the qualitative analysis of salt with cation \(y^{2+ },\) addition of a reagent (X) to alkaline solution of the salt gives a bright red precipitate. The reagent (X) and the cation \((y^{2+})\) respectively, are:

1. Dimethylglyoxime and \(Ni^{2+}\)
2. Dimethylglyoxime and \(Co^{2+}\)
3. Nessler's reagent and \(Hg^{2+}\)
4. Nessler's reagent and \(Ni^{2+}\)
Subtopic:  Detection of Cations |
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The incorrect statement among the following about the nitrate ion test is: 
1. A dark brown ring is formed at the junction of the two solutions.
2. Ring is formed due to the formation of nitroso ferrous sulphate complex. 
3. The brown complex is \([Fe(H_2O)_5~(NO)]SO_4.\)
4. Upon heating the nitrate salt with conc. \(H_2SO_4,\), light brown fumes are evolved. 
Subtopic:  Detection of Anions |
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On reaction with dilute \(H_2SO_4,\) which of the following salts will give out a gas that turns an acidified dichromate paper green?

(a) \(Na_2CO_3\)
(b) \(Na_2S\)
(c) \(ZnSO_3\)
(d) \(FeS\)

1. (b), (c), (d)
2. (b) and (c) 
3. (a), (b), (c)
4. None of the above
 
 
Subtopic:  Detection of Cations |
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The cation which gives yellow ppt with \(K_2CrO_4 \) in acetic acid is:

(a) \(Ba^{2+}\)
(b) \(Pb^{2+}\)
(c) \(Ca^{2+}\)
(d) \(Al^{3+}\)

1. (a) and (b)
2. (b) and (c) 
3. (a), (b), (c)
4.  (a), (b), (c) ,(d)
 
 
Subtopic:  Detection of Cations |
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