JEE Advanced · Chemistry · 20. Metallurgy
In the cyanide extraction process of silver from argentite ore, the oxidising and reducing agents used are
- A \(\mathrm{O}_{2}\) and \(\mathrm{CO}\) respectively
- B \(\mathrm{O}_{2}\) and \(\mathrm{Zn}\) dust respectively
- C \(\mathrm{HNO}_{3}\) and \(\mathrm{Zn}\) dust respectively
- D \(\mathrm{HNO}_{3}\) and \(\mathrm{CO}\) respectively
Answer & Solution
Correct Answer
(B) \(\mathrm{O}_{2}\) and \(\mathrm{Zn}\) dust respectively
Step-by-step Solution
Detailed explanation
The reactions involved in cyanide extraction process are:
\(\underset{\text { (argentite) }}{\mathrm{Ag}_{2} \mathrm{~S}}+4 \mathrm{NaCN} \rightarrow 2 \mathrm{Na}\left[\mathrm{Ag}(\mathrm{CN})_{2}\right]+\mathrm{Na}_{2} \mathrm{~S}\)
\(4 \mathrm{Na}_{2} \mathrm{~S}+\underset{\text { Oxiding agent }}{5 \mathrm{O}_{2}}+2 \mathrm{H}_{2} \mathrm{O} \rightarrow 2 \mathrm{Na}_{2} \mathrm{SO}_{4}~+\) \(4 \mathrm{NaOH}+2 \mathrm{~S}\)
\(2 \mathrm{Na}\left[\mathrm{Ag}(\mathrm{CN})_{2}\right]+\underset{\begin{array}{c}\text { (reducing } \\ \text { agent) }\end{array}}{\mathrm{Zn}} \rightarrow \mathrm{Na}_{2}\left[\mathrm{Zn}(\mathrm{CN})_{4}\right]\) \(+~2 \mathrm{Ag} \downarrow\)
\(\underset{\text { (argentite) }}{\mathrm{Ag}_{2} \mathrm{~S}}+4 \mathrm{NaCN} \rightarrow 2 \mathrm{Na}\left[\mathrm{Ag}(\mathrm{CN})_{2}\right]+\mathrm{Na}_{2} \mathrm{~S}\)
\(4 \mathrm{Na}_{2} \mathrm{~S}+\underset{\text { Oxiding agent }}{5 \mathrm{O}_{2}}+2 \mathrm{H}_{2} \mathrm{O} \rightarrow 2 \mathrm{Na}_{2} \mathrm{SO}_{4}~+\) \(4 \mathrm{NaOH}+2 \mathrm{~S}\)
\(2 \mathrm{Na}\left[\mathrm{Ag}(\mathrm{CN})_{2}\right]+\underset{\begin{array}{c}\text { (reducing } \\ \text { agent) }\end{array}}{\mathrm{Zn}} \rightarrow \mathrm{Na}_{2}\left[\mathrm{Zn}(\mathrm{CN})_{4}\right]\) \(+~2 \mathrm{Ag} \downarrow\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Chemistry
- Among the following, the correct statement(s) for electrons in an atom is(are)JEE Advanced 2024 Easy
- A solution of a metal ion when treated with \(\mathrm{KI}\) gives a red precipitate which dissolved in excess KI to give a colourless solution. Moreover, the solution of metal ion on treatment with a solution of cobalt (II) thiocyanate gives rise to a deep blue crystalline precipitqte. The metal ion isJEE Advanced 2007 Medium
- Consider the following statements related to colloids.
(I) Lyophobic colloids are not formed by simple mixing of dispersed phase and dispersion medium.
(II) For emulsions, both the dispersed phase and the dispersion medium are liquid.
(III) Micelles are produced by dissolving a surfactant in any solvent at any temperature.
(IV) Tyndall effect can be observed from a colloidal solution with dispersed phase having the same refractive index as that of the dispersion medium.
The option with the correct set of statements isJEE Advanced 2023 Medium - Liquids A and B form ideal solution over the entire range of composition. At temperature , equimolar binary solution of liquids A and B has vapour pressure . At the same temperature, a new solution of A and B having mole fractions , respectively, has vapour pressure of . The value of , in the new solution is ____.
(Given that the vapour pressure of pure liquid A is at temperature )JEE Advanced 2018 Medium - \(\mathrm{Ag}^{+}+\mathrm{NH}_3 \rightleftharpoons\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)\right]^{+} ; k_1=3.5 \times 10^{-3}\) \(\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)\right]^{+}+\mathrm{NH}_3 \rightleftharpoons\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)_2\right]^{+} ; k_2\) \(=1.7 \times 10^{-3}\) then the formation constant of \(\left[\mathrm{Ag}\left(\mathrm{NH}_3\right)_2\right]^{+}\)isJEE Advanced 2006 Medium
- The correct statement(s) pertaining to the adsorption of a gas on a solid surface is(are)JEE Advanced 2011 Hard
More PYQs from JEE Advanced
- Match the Statements/Expressions in Column I with the Statements/Expressions in Column II.
Column I Column II (A) The minimum value of \(\frac{x^2+2 x+4}{x+2}\) is (p) 0 (B) Let \(A\) and \(B\) be \(3 \times 3\) matrices of real numbers, where \(A\) is symmetric, \(B\) is skew-symmetric and \((A+B)(A-B) =\) \((A-B)(A+B)\). If \((A B)^t=(-1)^k\) \(A B\), where \((A B)^t\) is the transpose of the matrix \(A B\), then possible values of \(k\) are (q) 1 (C) Let \(a=\log _3 \log _3 2\). An integer \(k\) satisfying \(1<2^{\left(-k+3^{-a}\right)}<2\), must be less than (r) 2 (D) If \(\sin \theta=\cos \phi\), then the possible values of \(\frac{1}{\pi}\left(\theta \pm \phi-\frac{\pi}{2}\right)\) are (s) 3 JEE Advanced 2008 Hard - Match the column.
Normals at \(P, Q, R\) are drawn to \(y^2=4 x\) which intersect at \((3,0)\). Then,
JEE Advanced 2006 Medium - \[
\text { Match the statements/expressions in Column I with the open intervals in Column II. }
\]
JEE Advanced 2009 Hard - Let be the set of all complex numbers satisfying If the complex number is such that is the maximum of the set then the principal argument of isJEE Advanced 2019 Medium
- A liquid at is poured very slowly into a Calorimeter that is at temperature of The boiling temperature of the liquid is It is found that the first of the liquid completely evaporates. After pouring another of the liquid the equilibrium temperature is found to be The ratio of the Latent heat of the liquid to its specific heat will be ______
[Neglect the heat exchange with surrounding]JEE Advanced 2019 Medium - During sodium nitroprusside test of sulphide ion in an aqueous solution, one of the ligands coordinated to the metal ion is converted toJEE Advanced 2025 Easy