Principles of Qualitative Analysis

During sodium nitroprusside test of sulphide ion in an aqueous solution, one of the ligands coordinated to the metal ion is converted to

Which of the following compounds is/are yellow in colour? (memory based jee mains shift-2 28/01/2025)

\(\left(\mathrm{a}\right)\mathrm{CdS}\\ \left(\mathrm{b}\right)\mathrm{PbS}\\ \left(\mathrm{c}\right)\mathrm{CuS}\\ \left(\mathrm{d}\right)\mathrm{ZnS}(\mathrm{cold})\\ \left(\mathrm{e}\right){\mathrm{PbCrO}}_{4}\)

Yellow compound of lead chromate gets dissolved on treatment with hot \(\mathrm{NaOH}\) solution. The product of lead formed is a

[JEE Main 2024, 27 Jan (Shift 1)]

The metal ion whose electronic configuration is not affected by the nature of the ligand and which gives a violet colour in non-luminous flame under hot condition in borax bead test is

[JEE Main 2025, 28 Jan (Shift 1)]

When \(Mn{O}_{2}\) and \({H}_{2}S{O}_{4}\) is added to a salt (A), the greenish yellow gas liberated as salt (A) isEndFragment

[JEE Main 2024, 04 Apr (Shift 2)]

When \(Mn{O}_{2}\) and \({H}_{2}S{O}_{4}\) is added to a salt (A), the greenish yellow gas liberated as salt (A) isEndFragment

[JEE Main 2024, 04 Apr (Shift 2)]

Choose the correct tests with respective observations.
(A) \({\mathrm{CuSO}}_{4}\) (acidified with acetic acid) + \({\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\to\)Chocolate brown precipitate.
(B) \({\mathrm{FeCl}}_{3}+{\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\to\) Prussian blue precipitate.
(C) \({\mathrm{ZnCl}}_{2}+{\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\), neutralised with \({\mathrm{NH}}_{4}\mathrm{OH}\to\) White or bluish white precipitate.
(D) \({\mathrm{MgCl}}_{2}+{\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\to\) Blue precipitate.
(E) \({\mathrm{BaCl}}_{2}+{\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\), neutralised with \(\mathrm{NaOH}\to\) White precipitate.
Choose the correct answer from the options given below :

During the detection of acidic radical present in a salt, a student gets a pale yellow precipitate soluble with difficulty in \(NH _4 OH\) solution when sodium carbonate extract was first acidified with dil. \(HNO _3\) and then \(AgNO _3\) solution was added. This indicates presence of

[JEE Main 2024, 06 Apr (Shift 2)]

During the detection of acidic radical present in a salt, a student gets a pale yellow precipitate soluble with difficulty in \(NH _4 OH\) solution when sodium carbonate extract was first acidified with dil. \(HNO _3\) and then \(AgNO _3\) solution was added. This indicates presence of

[JEE Main 2024, 06 Apr (Shift 2)]

Consider three metal chlorides x, y and z, where x is water soluble at room temperature, y is sparingly soluble in water at room temperature and z is soluble in hot water. x, y and z are respectively

Identify the inorganic sulphides that are yellow in colour :
(A) \({\left(N{H}_{4}\right)}_{2}S\)
(B) PbS
(C) CuS
(D) \(A{s}_{2}{S}_{3}\)
(E) \(A{s}_{2}{S}_{5}\)

Choose the correct answer from the options given below

[JEE Main 2025, 28 Jan (Shift 2)]

While preparing crystals of Mohr's salt, dil \({H}_{2}S{O}_{4}\) is added to a mixture of ferrous sulphate and ammonium sulphate, before dissolving this mixture in water, dil \({H}_{2}S{O}_{4}\) is added here to :

[JEE Main 2024, 05 Apr (Shift 2)]

While preparing crystals of Mohr's salt, dil \({H}_{2}S{O}_{4}\) is added to a mixture of ferrous sulphate and ammonium sulphate, before dissolving this mixture in water, dil \({H}_{2}S{O}_{4}\) is added here to :

[JEE Main 2024, 05 Apr (Shift 2)]

In the Group analysis of cations, Ba²⁺ & Ca²⁺ are precipitated respectively as

During sodium nitroprusside test of sulphide ion in an aqueous solution, one of the ligands coordinated to the metal ion is converted to

[JEE Advanced 2025, Paper-2]

Consider the following reactions

\({\mathrm{Na}}_{2}{\mathrm{B}}_{4}{\mathrm{O}}_{7}\overset{\Delta }{\to }2\mathrm{X}+\mathrm{Y}\)

\({\mathrm{CuSO}}_{4}\text{ }+\text{ }\mathrm{Y}\text{ }\overset{\mathrm{Non}−\mathrm{Luminous}\text{  }\mathrm{flame}}{\to }\mathrm{Z}+{\mathrm{SO}}_{3}\)

\(2\mathrm{Z}+2\mathrm{X}\text{ }+\text{ }\mathrm{Carbon}\text{ }\overset{\mathrm{Luminous}\text{  }\mathrm{flame}}{\to }2\mathrm{Q}\text{  }+\text{ }{\mathrm{Na}}_{2}{\mathrm{B}}_{4}{\mathrm{O}}_{7}+\mathrm{CO}\)

The oxidation states of Cu in Z and Q, respectively are:

[JEE Main 2026, 28 Jan (Shift 2)]

Which of the following is yellow colored? (memory based jee mains shift-2 24/01/2025)

Assertion (A): The gas liberated on warming a salt with dil \(\mathrm{H}_2 \mathrm{SO}_4\), turns a piece of paper dipped in lead acetate into black, it is a confirmatory test for sulphide ion.

Reason (R): In statement-I the colour of paper turns black because of formation of lead sulphite.

[JEE Main 2024, 30 Jan (Shift 1)]

Formation of \({\mathrm{Na}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{5}\mathrm{NOS}\right]\), a purple coloured complex formed by addition of sodium nitroprusside in sodium carbonate extract of salt indicates the presence of :

[JEE Main 2025, 2 Apr (Shift 2)]

The metal ion whose electronic configuration is not affected by the nature of the ligand and which gives a violet colour in non-luminous flame under hot condition in borax bead test is

A first row transition metal (M) does not liberate H₂ gas from dilute HCl. 1 mol of aqueous solution of MSO₄ is treated with excess of aqueous KCN and then H₂S(g) is passed through the solution. The amount of MS (metal sulphide) formed from the above reaction is___mol.

[JEE Main 2026, 22 Jan (Shift 1)]

Why \({\mathrm{NH}}_{4}\mathrm{Cl}\) is added before \({\mathrm{NH}}_{4}\mathrm{OH}\) for the ppt. of \({\mathrm{Fe}}^{3+}\) ions?

Among the following cations, the number of cations which will give characteristic precipitate in their identification tests with \({K}_{4}\left[Fe(CN{)}_{6}\right]\) is ______

\(C{u}^{2+},F{e}^{3+},B{a}^{2+},C{a}^{2+},N{H}_{4}^{+},M{g}^{2+},Z{n}^{2+}\)

[JEE Main 2025, 24 Jan (Shift 1)]

On passing a gas, 'X', through nessler's reagent, a brown precipitate is obtained. The gas 'X' is

[JEE Main 2024, 29 Jan (Shift 2)]

Consider the following reactions

\({\mathrm{Na}}_{2}{\mathrm{B}}_{4}{\mathrm{O}}_{7}\overset{\Delta }{\to }2\mathrm{X}+\mathrm{Y}\)

\({\mathrm{CuSO}}_{4}\text{ }+\text{ }\mathrm{Y}\text{ }\overset{\mathrm{Non}−\mathrm{Luminous}\text{  }\mathrm{flame}}{\to }\mathrm{Z}+{\mathrm{SO}}_{3}\)

\(2\mathrm{Z}+2\mathrm{X}\text{ }+\text{ }\mathrm{Carbon}\text{ }\overset{\mathrm{Luminous}\text{  }\mathrm{flame}}{\to }2\mathrm{Q}\text{  }+\text{ }{\mathrm{Na}}_{2}{\mathrm{B}}_{4}{\mathrm{O}}_{7}+\mathrm{CO}\)

The oxidation states of Cu in Z and Q, respectively are:

[JEE Main 2026, 28 Jan (Shift 2)]

Why \({\mathrm{NH}}_{4}\mathrm{Cl}\) is added before \({\mathrm{NH}}_{4}\mathrm{OH}\) for the ppt. of \({\mathrm{Fe}}^{3+}\) ions?

A first row transition metal (M) does not liberate H₂ gas from dilute HCl. 1 mol of aqueous solution of MSO₄ is treated with excess of aqueous KCN and then H₂S(g) is passed through the solution. The amount of MS (metal sulphide) formed from the above reaction is___mol.

[JEE Main 2026, 22 Jan (Shift 1)]

Formation of \({\mathrm{Na}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{5}\mathrm{NOS}\right]\), a purple coloured complex formed by addition of sodium nitroprusside in sodium carbonate extract of salt indicates the presence of :

[JEE Main 2025, 2 Apr (Shift 2)]

Choose the correct tests with respective observations.
(A) \({\mathrm{CuSO}}_{4}\) (acidified with acetic acid) + \({\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\to\)Chocolate brown precipitate.
(B) \({\mathrm{FeCl}}_{3}+{\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\to\) Prussian blue precipitate.
(C) \({\mathrm{ZnCl}}_{2}+{\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\), neutralised with \({\mathrm{NH}}_{4}\mathrm{OH}\to\) White or bluish white precipitate.
(D) \({\mathrm{MgCl}}_{2}+{\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\to\) Blue precipitate.
(E) \({\mathrm{BaCl}}_{2}+{\mathrm{K}}_{4}\left[\mathrm{Fe}(\mathrm{CN}{)}_{6}\right]\), neutralised with \(\mathrm{NaOH}\to\) White precipitate.
Choose the correct answer from the options given below :

The oxidation number of iron in the compound formed during brown ring test for \(NO _3^{-}\)ion is _______

[JEE Main 2024, 29 Jan (Shift 2)]

The metal ion whose electronic configuration is not affected by the nature of the ligand and which gives a violet colour in non-luminous flame under hot condition in borax bead test is

Identify the inorganic sulphides that are yellow in colour

(A) \({\left({\mathrm{NH}}_{4}\right)}_{2}\mathrm{S}\)
(B) PbS
(C) CuS
(D) \(A{s}_{2}{S}_{3}\)
(E) \(A{s}_{2}{S}_{5}\)

Choose the correct answer from the options given below

[JEE Main 2025, 28 Jan (Shift 2)]

In the Group analysis of cations, Ba²⁺ & Ca²⁺ are precipitated respectively as

Statement (I) : Colourless cupric metaborate is reduced to cuprous metaborates in a luminous flame.

Statement (II) : Cuprous metaborates is obtained by heating Boric anhydride and copper sulphate in a non-luminous flame

[JEE Main 2021, 24 Feb (Shift 1)]

When a solution of mixture having two inorganic salts was treated with freshly prepared ferrous sulphate in acidic medium, a dark brown ring was formed whereas on treatment with neutral \({\mathrm{FeCl}}_{3}\) , it gave deep red colour which disappeared on boiling and a brown red ppt was formed. The mixture contains

[JEE Main 2023, 11 Apr (Shift 1)]

Formulae for Nessler's reagent is:

[JEE Main 2023, 30 Jan (Shift 2)]

The reaction of \({\mathrm{K}}_{3}\left[\mathrm{Fe}{\left(\mathrm{CN}\right)}_{6}\right]\) with freshly prepared \({\mathrm{FeSO}}_{4}\) solution produces a dark blue precipitate called Turnbull's blue, Reaction of \({\mathrm{K}}_{4}\left[\mathrm{Fe}{\left(\mathrm{CN}\right)}_{6}\right]\) with the \({\mathrm{FeSO}}_{4}\) solution in complete absence of air produces a white precipitate X, which turns blue in air. Mixing the \({\mathrm{FeSO}}_{4}\) solution with \({\mathrm{NaNO}}_{3}\), followed by a slow addition of concentrated \({\mathrm{H}}_{2}{\mathrm{SO}}_{4}\) through the side of the test tube produces a brown ring. Precipitate X is

[JEE Advanced 2021, Paper-2]

In the wet tests for identification of various cations by precipitation, which transition element cation doesn't belong to group IV in qualitative inorganic analysis?

[JEE Main 2023, 30 Jan (Shift 1)]

During the qualitative analysis of \(SO _3^{2-}\) using dilute \(H _2 SO _4, SO _2\) gas is evolved which turns \(K _2 Cr _2 O _7\) solution (acidified with dilute \(H _2 SO _4\) ):

[JEE Main 2023, 30 Jan (Shift 1)]

When Cu²⁺ ion is treated with KI, a white precipitate, X appears in solution. The solution is titrated with sodium thiosulphate, the compound Y is formed. X and Y respectively are

During the borax bead test with \(\mathrm{CuSO}_4\), a blue green colour of the bead was observed in oxidising flame due to the formation of

[JEE Main 2023, 29 Jan (Shift 1)]

The reaction of \({\mathrm{K}}_{3}\left[\mathrm{Fe}{\left(\mathrm{CN}\right)}_{6}\right]\) with freshly prepared \({\mathrm{FeSO}}_{4}\) solution produces a dark blue precipitate called Turnbull's blue, Reaction of \({\mathrm{K}}_{4}\left[\mathrm{Fe}{\left(\mathrm{CN}\right)}_{6}\right]\) with the \({\mathrm{FeSO}}_{4}\) solution in complete absence of air produces a white precipitate X, which turns blue in air. Mixing the \({\mathrm{FeSO}}_{4}\) solution with \({\mathrm{NaNO}}_{3}\), followed by a slow addition of concentrated \({\mathrm{H}}_{2}{\mathrm{SO}}_{4}\) through the side of the test tube produces a brown ring. Precipitate X is

Match column-I with column-II:

Choose the most appropriate answer from the options given below:

In the wet tests for detection of various cations by precipitation, \(Ba ^{2+}\) cations are detected by obtaining precipitate of

[JEE Main 2023, 13 Apr (Shift 2)]

In the scheme given below, X and Y, respectively, are

Metal halide \(\overset{\mathrm{aq}.\mathrm{NaOH}}{\to }\) White Precipate (P) + Filtrate (Q)

\(\mathrm{P}\overset{\begin{matrix}\mathrm{aq}.\text{ }{\mathrm{H}}_{2}{\mathrm{SO}}_{4} \\ {\mathrm{PbO}}_{2}(\mathrm{excess})\end{matrix}}{\underset{\mathrm{heat}}{\to }}\mathrm{X}\)(a coloured species in solution)

\(\mathrm{Q}\overset{\begin{matrix}\mathrm{MnO}{(\mathrm{OH})}_{2} \\ \mathrm{Conc}.\text{​ }{\mathrm{H}}_{2}{\mathrm{SO}}_{4}\end{matrix}}{\underset{\mathrm{warm}}{\to }}\mathrm{Y}\) (gives blue-colouation with KI-starch paper)

Which element is not present in Nessler's reagent?

[JEE Main 2023, 1 Feb (Shift 2)]

An inorganic compound ' X ' on treatment with concentrated \({H}_{2}S{O}_{4}\) produces brown fumes and gives dark brown ring with \(FeS{O}_{4}\) in presence of concentrated \({H}_{2}S{O}_{4}\). Also compound ' X ' gives precipitate ' Y ', when its solution in dilute HCl is treated with \({H}_{2}S\) gas. The precipitate ' Y ' on treatment with concentrated \(HN{O}_{3}\) followed by excess of \(N{H}_{4}OH\) further gives deep blue coloured solution, Compound ' X ' is:

[JEE Main 2021, 20 Jul (Shift 1)]

An inorganic compound ' \(X\) ' on treatment with concentrated \(H _2 SO _4\) produces brown fumes and gives dark brown ring with \(FeSO _4\) in presence of concentrated \(H _2 SO _4\). Also compound ' \(X\) ' gives precipitate ' \(Y\) ', when its solution in dilute \(HCl\) is treated with \(H _2 S\) gas. The precipitate ' \(Y\) ' on treatment with concentrated \(HNO _3\) followed by excess of \(NH _4 OH\) further gives deep blue coloured solution, Compound ' \(X\) ' is:

Formation of which complex, among the following, is not a confirmatory test of \(Pb ^{2+}\) ions

[JEE Main 2023, 6 Apr (Shift 2)]

Statement I: Upon heating a borax bead dipped in cupric sulphate in a luminous flame, the colour of the bead becomes green.
Statement II : The green colour observed is due to the formation of copper(I) metaborate. In the light of the above statements, choose the most appropriate answer from the options given below: