Nessler's reagent is used to detect:
 
1. \(CrO^{2-}_4\)
2. \(PO^{3-}_4\)
3. \(MnO^{-}_4\)
4. \(NH^{+}_4\)

Subtopic:  Detection of Cations |
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A gas (X) is passed through water to form a saturated solution. The aqueous solution on treatment with silver nitrate gives a white precipitate. The saturated aqueous solution also dissolves magnesium ribbon with the evolution of a colourless gas (Y). X and Y, respectively, are:
1. \(X= CO_2,~Y=Cl_2 \)
2. \(X= Cl_2,~Y=CO_2 \)
3. \(X= Cl_2,~Y=H \)
4. \(X= H,~Y=Cl_2 \)
Subtopic:  Detection of Anions |
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\(Cu^{2+}\) ions can be reduced to \(Cu^{+}\) ions by the addition of an aqueous solution of: 

1. \(KF \)
2. \(KCl \)
3. \(KI \)
4. \(KOH \)
Subtopic:  Detection of Cations | Detection of Anions |
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A basic radical among the following that cannot be precipitated by
\(H_2S \) gas in the presence of \(NH_3 \) is:

1. \(Mn^{2+}\)
2. \(Ni^{2+}\)
3. \(Cd^{2+}\)
4. \(Ca^{2+}\)
Subtopic:  Detection of Cations |
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A metal nitrate reacts with \(Kl \) to give a black precipitate which upon additionof excess
of \(Kl\) converts into orange colour solution. The cation of the metal nitrate is: 

1. \(Hg^{2+}\)
2. \(Bi^{3+}\)
3. \(Pb^{2+}\)
4. \(Cu^+\)
Subtopic:  Detection of Cations |
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The reagents, \(NH_4Cl\) and aqueous \(NH_3\), will precipitate:

1. \(Ca^{2+}\)
2. \(Al^{3+}\)
3. \(B i^{3+}\)
4. \(Mg^{2+} \)
Subtopic:  Detection of Cations |
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Which of the following reagents can be used to distinguish between sulphite and sulphate ions present in a solution?
1. \(FeSO_4\)
2. \(Na_2[FeI(CN)_5NO] \)
3. \(BaCl_2 \)
4. \(Na_3[Co(NO_2)6] \)
Subtopic:  Detection of Anions |
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\(Na_2CO_3 \) cannot be used in place of \((NH_4)_2CO_3 \) for the precipitation of fifth group radicals.
This is because: 

1. Magnesium will precipitate 
2. The concentration of carbonate ions is very low
3. Sodium ions will react with acidic radicals 
4. \(Na^{+} \) ions interfere with the detection of the fifth group 
Subtopic:  Detection of Cations |
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A metal sulphate (A) on heating evolves two gases (B) and (C) and an oxide (D).
Gas (B) turns \(K_2Cr_2O_7\) paper green while gas (C) forms a trimer in which there
is no \(S-S\) bond. Oxide (D) with conc. \(HCl\) forms a Lewis acid (E) which exists
in a dimer. Compounds (A), (B), (C), (D) and (E), respectively, are:

1. \(FeSO_4, SO_2,Fe_2O_3,FeCl_3\)
2. \(Al_2(SO_4)_3,SO_2,SO_3,Al_2O_3,FeCl_3\)
3. \(FeS,SO_2,SO_3,FeSO_4,FeCl_3\)
4. \(FeS,SO_2,SO_3,Fe_2(PO_4)_3,FeCl_2\)
Subtopic:  Detection of Cations |
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In this sequence, X, Y, Z are, respectively,: 


1. Acidified \(H_2O_2;\) Alkaline \(H_2O_2;\) Acidified \(H_2O_2\)
2. Alkaline \(H_2O_2;\) Acidified \(H_2O_2;~Zn/HCl.\)
3. Acidified \(H_2O_2;\) Heat; Alkaline \(H_2O_2\)
4. Alkaline \(H_2O_2;\) Acidified \(H_2O_2;\) on standing  
Subtopic:  Detection of Cations |
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