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Molar mass of the salt from \( \mathrm{NaBr} \), \( \mathrm{NaNO_3} \), \( \mathrm{KI} \) and \( \mathrm{CaF_2} \) which does not evolve coloured vapours on heating with concentrated \( \mathrm{H_2SO_4} \) is ______ \( \mathrm{g \, mol^{-1}} \).
(Molar mass in \( \mathrm{g \, mol^{-1}} \): \( \mathrm{Na}: 23 \), \( \mathrm{N}: 14 \), \( \mathrm{K}: 39 \), \( \mathrm{O}: 16 \), \( \mathrm{Br}: 80 \), \( \mathrm{I}: 127 \), \( \mathrm{F}: 19 \), \( \mathrm{Ca}: 40 \))

\( \mathrm{NaCl} \) reacts with conc. \( \mathrm{H_2SO_4} \) and \( \mathrm{K_2Cr_2O_7} \) to give reddish fumes \( (B) \), which react with \( \mathrm{NaOH} \) to give yellow solution \( (C) \). \( (B) \) and \( (C) \) respectively are:

The oxidation number of iron in the compound formed during brown ring test for \( \mathrm{NO_3^-} \) ion is _______.

A reagent which gives brilliant red precipitate with Nickel ions in basic medium is:

Consider the following test for a group-\( \text{IV} \) cation.
\( \text{M}^{2+} + \text{H}_2\text{S} \rightarrow \text{A} \) (Black precipitate) \( + \) byproduct
\( \text{A} + \) aqua regia \( \rightarrow \text{B} + \text{NOCl} + \text{S} + \text{H}_2\text{O} \)
\( \text{B} + \text{KNO}_2 + \text{CH}_3\text{COOH} \rightarrow \text{C} + \) byproduct
The spin-only magnetic moment value of the metal complex \( \text{C} \) is __ \( \text{BM} \) (Nearest integer)

Given below are two statements:
Statement (I): The gas liberated on warming a salt with dil \( \mathrm{H_2SO_4} \), turns a piece of paper dipped in lead acetate into black, it is a confirmatory test for sulphide ion.
Statement (II): In statement-I the colour of paper turns black because of formation of lead sulphite. In the light of the above statements, choose the most appropriate answer from the options given below:

The number of white coloured salts, among the following is _______.
(a) \( \mathrm{SrSO_4} \) (b) \( \mathrm{Mg(NH_4)PO_4} \) (c) \( \mathrm{BaCrO_4} \) (d) \( \mathrm{Mn(OH)_2} \)
(e) \( \mathrm{PbSO_4} \) (f) \( \mathrm{PbCrO_4} \) (g) \( \mathrm{AgBr} \) (h) \( \mathrm{PbI_2} \)
(i) \( \mathrm{CaC_2O_4} \) (j) \( [\mathrm{Fe(OH)_2(CH_3COO)}] \)

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

The compound that is white in color is:

In the precipitation of the iron group \( (\text{III}) \) in qualitative analysis, ammonium chloride is added before adding ammonium hydroxide to:

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

Given below are two statements:

Statement I: On passing \( \mathrm{HCl_{(g)}} \) through a saturated solution of \( \mathrm{BaCl_2} \) at room temperature white turbidity appears.
Statement II: When \( \mathrm{HCl} \) gas is passed through a saturated solution of \( \mathrm{NaCl} \), sodium chloride is precipitated due to common ion effect.
In the light of the above statements, choose the most appropriate answer from the options given below:

In a borax bead test under hot condition, a metal salt (one from the given) is heated at point B of the flame, resulted in green colour salt bead. The spin-only magnetic moment value of the salt is __________ \( \text{BM} \) (Nearest integer) [Given atomic number of Cu = \( 29 \), Ni = \( 28 \), Mn = \( 25 \), Fe = \( 26 \)].

During the detection of acidic radical present in a salt, a student gets a pale yellow precipitate soluble with difficulty in \( \mathrm{NH_4OH} \) solution when sodium carbonate extract was first acidified with dil. \( \mathrm{HNO_3} \) and then \( \mathrm{AgNO_3} \) solution was added. This indicates presence of:

The azo-dye (Y) formed in the following reaction is.
Sulphanilic acid + \( \text{NaNO}_2 \) + \( \text{CH}_3\text{COOH} \) \( \rightarrow \) X.

Number of metal ions characterized by flame test among the following is ________.
\( \mathrm{Sr^{2+}} \), \( \mathrm{Ba^{2+}} \), \( \mathrm{Ca^{2+}} \), \( \mathrm{Cu^{2+}} \), \( \mathrm{Zn^{2+}} \), \( \mathrm{Co^{2+}} \), \( \mathrm{Fe^{2+}} \)

While preparing crystals of Mohr's salt, dil \( \mathrm{H_2SO_4} \) is added to a mixture of ferrous sulphate and ammonium sulphate, before dissolving this mixture in water, dil \( \mathrm{H_2SO_4} \) is added here to:

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JEE Main 2024 4th April Morning Shift

In the precipitation of the iron group \( (\text{III}) \) in qualitative analysis, ammonium chloride is added before adding ammonium hydroxide to: