Select Chapter Topics:
Q. No.Which of the following anions gives colourless gas during the preliminary test?
(a) \(SO^{2-}_3\)
(b) \(SO^{2-} _4\)
(c) \(NO^-_2 \)
(d) \(CH_3COO^- \)
1. (a), (b) and (d)
2. (b) and (c)
3. (a), (b) and (c)
4. None of the above
Subtopic: Detection of Anions | Detection of extra elements |
70%
Level 2: 60%+
Hints
Which of the following cations precipitate as their chlorides?
(a) \(Pb^{2+}\)
(b) \(Ag^{+}\)
(c) \(Hg^{2+}_2\)
(d) \(Cd^{2+}\)
1. (a), (b), (d)
2. (b) and (c)
3. (a), (b), (c)
4. None of the above
(a) \(Pb^{2+}\)
(b) \(Ag^{+}\)
(c) \(Hg^{2+}_2\)
(d) \(Cd^{2+}\)
1. (a), (b), (d)
2. (b) and (c)
3. (a), (b), (c)
4. None of the above
Subtopic: Detection of Cations |
75%
Level 2: 60%+
Hints
A white sublimable solid, when boiled with an \(NaOH\) solution, gives a colourless gas that turns Nessler's reagent brown. The solid, on being heated with solid \(K_2Cr_2O_7\) and concentrated \(H_2SO_4,\) gives red brown vapours. The white solid can be :
(a) \(NH_4I\)
(b) \(NH_4Br\)
(c) \(NH_4Cl\)
(d) \((NH_4)_2SO_4\)
1. (a), (b), (d)
2. (b) and (c)
3. (a), (b), (c)
4. None of the above
(a) \(NH_4I\)
(b) \(NH_4Br\)
(c) \(NH_4Cl\)
(d) \((NH_4)_2SO_4\)
1. (a), (b), (d)
2. (b) and (c)
3. (a), (b), (c)
4. None of the above
Subtopic: Detection of Cations |
53%
Level 3: 35%-60%
Hints
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) and (c)
4. (a), (b), (c) and (d)
(a) \(Ba^{2+}\)
(b) \(Pb^{2+}\)
(c) \(Ca^{2+}\)
(d) \(Al^{3+}\)
1. (a) and (b)
2. (b) and (c)
3. (a), (b) and (c)
4. (a), (b), (c) and (d)
Subtopic: Detection of Cations |
Level 3: 35%-60%
Hints
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
(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 |
64%
Level 2: 60%+
Hints
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. (b) Only
(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. (b) Only
Subtopic: Detection of Cations |
65%
Level 2: 60%+
Hints
Incorrect statements among the following are:
1. (a), (b) and (d)
2. (c) and (d)
3. (a), (b) and (c)
4. (a), (b), (c) and (d)
| (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 |
2. (c) and (d)
3. (a), (b) and (c)
4. (a), (b), (c) and (d)
Subtopic: Detection of Cations |
61%
Level 2: 60%+
Hints
\(Fe^{3+},Zn^{2+}\) 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
1. \(2M~HCl \)
2. \(6M~NH_3 \)
3. \(6M~NaOH \)
4. \(H_2S~\) gas
Subtopic: Detection of Cations |
Level 3: 35%-60%
Hints
An aqueous solution of a substance gives a white precipitate on treatment with dilute hydrochloric acid, which dissolves on heating. When 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
The substance is a:
1. \(Hg^{2+}_2\) salt
2. \(Cu^{2+}\) salt
3. \(Ag^+\) salt
4. \(Pb^{2+}\) salt
Subtopic: Detection of Cations |
74%
Level 2: 60%+
Hints
A solution when diluted with \(H_2O\) and boiled, gives a white precipitate. Upon addition of excess \(NH_4Cl/NH_4OH, \)the volume of precipitate decreases, leaving behind a white gelatinous precipitate. Identify the precipitate that dissolves :
1. \(Al(OH)_3\)
2. \(Z n(OH)_2\)
3. \(Ca(OH)_2\)
4. \(Mg(OH)_2\)
1. \(Al(OH)_3\)
2. \(Z n(OH)_2\)
3. \(Ca(OH)_2\)
4. \(Mg(OH)_2\)
Subtopic: Detection of Cations |
Level 3: 35%-60%
Hints
Select Chapter Topics:
© 2025 GoodEd Technologies Pvt. Ltd.