Chapter 22

One of the constituent of German silver is (a) \(\mathrm{Ag}\) (b) \(\mathrm{Cu}\) (c) \(\mathrm{Mg}\) (d) \(\mathrm{Al}\)

Which of the following is the weakest base (a) \(\mathrm{NaOH}\) (b) \(\mathrm{Ca}(\mathrm{OH})_{2}\) (c) \(\mathrm{KOH}\) (d) \(\mathrm{Zn}(\mathrm{OH})_{2}\)

An acidified solution of potassium chromate was layered with an equal volume of amyl alcohol. When it was shaken after the addition of \(1 \mathrm{~mL}\) of \(3 \% \mathrm{H}_{2} \mathrm{O}_{2}\), a blue alcohol layer was obtained. The blue color is due to the formation of a chromium (VI) compound ' \(\mathbf{X}\). What is the number of oxygen atoms bonded to chromium through only single bonds in a molecule of \(\mathbf{X}\) ?

Consider the following list of reagents: [Adv. 2014] Acidified \(\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\), alkaline \(\mathrm{KMnO}_{4}, \mathrm{CuSO}_{4}, \mathrm{H}_{2} \mathrm{O}_{2}, \mathrm{Cl}_{2}, \mathrm{O}_{3}, \mathrm{FeCl}_{3}, \mathrm{HNO}_{3}\) and \(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) The total number of reagents that can oxidise aqueous iodide to iodine is

Silver chloride is sparingly soluble in water because its lattice energy is greater than ........... energy.

Galvanization of iron denotes coating with ............... .

\(\mathrm{Mn}^{2+}\) can be oxidised to \(\mathrm{Mn} \mathrm{O}_{4}^{-}\)by \(\ldots \ldots \ldots \ldots \ldots .\) \(\left(\mathrm{SnO}_{2}, \mathrm{PbO}_{2}, \mathrm{BaO}_{2}\right)\)

Fusion of \(\mathrm{MnO}_{2}\) with \(\mathrm{KOH}\) in presence of \(\mathrm{O}_{2}\) produces a salt \(W\). Alkaline solution of \(W\) upon electrolytic oxidation yields another salt\(X\). The manganese containing ions present in \(\mathrm{W}\) and \(X\), respectively are \(Y\) and \(Z\). Correct statement(s) is (are) (a) In both \(Y\) and \(Z\), p-bonding occurs between \(p\)-orbitals of oxygen and \(d\) orbitals of manganese (b) In aqueous acidic solution, \(Y\) undergoes dispro-portionation reaction to give \(Z\) and \(\mathrm{MnO}_{2}\) (c) Both \(Y\) and \(Z\) are coloured and have tetrahedral shape (d) \(Y\) is diamagnetic in nature while \(Z\) is paramagnetic

\(\mathrm{Fe}^{3+}\) is reduced to \(\mathrm{Fe}^{2+}\) by using (a) \(\mathrm{H}_{2} \mathrm{O}_{2}\) in presence of \(\mathrm{NaOH}\) (b) \(\mathrm{Na}_{2} \mathrm{O}_{2}\) in water (c) \(\mathrm{H}_{2} \mathrm{O}_{2}\) in presence of \(\mathrm{H}_{2} \mathrm{SO}_{4}\) (d) \(\mathrm{Na}_{2} \mathrm{O}_{2}\) in presence of \(\mathrm{H}_{2} \mathrm{SO}_{4}\)

The correct statement(s) about \(\mathrm{Cr}^{2+}\) and \(\mathrm{Mn}^{3+}\) is (are) [Atomic numbers of \(\mathrm{Cr}=24\) and \(\mathrm{Mn}=25\) ] (a) \(\mathrm{Cr}^{2+}\) is a reducing agent (b) \(\mathrm{Mn}^{3+}\) is an oxidizing agent (c) Both \(\mathrm{Cr}^{2+}\) and \(\mathrm{Mn}^{3+}\) exhibit \(d^{4}\) electronic configuration (d) When \(\mathrm{Cr}^{2+}\) is used as a reducing agent, the chromium ion attains \(d^{5}\) electronic configuration

The pair(s) of reagents that yield paramagnetic speciesis/are (a) Na and excess of \(\mathrm{NH}_{3}\) (b) \(\mathrm{K}\) and excess of \(\mathrm{O}_{2}\) (c) \(\mathrm{Cu}\) and dilute \(\mathrm{HNO}_{3}\) (d) \(\mathrm{O}_{2}\) and 2 -ethylanthraquinol

Reduction of the metal centre in aqueous permanganate ion involves (a) 3 electrons in neutral medium (b) 5 electrons in neutral medium (c) 3 electrons in alkaline medium (d) 5 electrons in acidic medium

Addition of high proportions of manganese makes steel useful in making rails of railroads, because manganese (a) gives hardness to steel (b) helps the formation of oxides of iron (c) can remove oxygen and sulphur (d) can show highest oxidation state of \(+7\).

Which of the following alloys contain(s) \(\mathrm{Cu}\) and \(\mathrm{Zn}\) ? (a) Bronze (b) Brass (c) Gun metal (d) Type metal

The aqueous solutions of the following salts will be coloured in the case of (a) \(\mathrm{Zn}\left(\mathrm{NO}_{3}\right)_{2}\) (b) \(\mathrm{LiNO}_{3}\) (c) \(\mathrm{Co}\left(\mathrm{NO}_{3}\right)_{2}\) (d) \(\mathrm{CrCl}_{3}\) (e) Potash alum

Potassium manganate \(\left(\mathrm{K}_{2} \mathrm{MnO}_{4}\right)\) is formed when (a) chlorine is passed into aqueous \(\mathrm{KMnO}_{4}\) solution (b) manganese dioxide is fused with potassium hydroxide in air (c) formaldehyde reacts with potassium permanganate in presence of a strong alkali (d) potassium permanganate reacts with conc. sulphuric acid

Match each of the reactions given in Column I with the corresponding product(s) given in Column II. Column I (A) \(\mathrm{Cu}+\mathrm{dil} \mathrm{HNO}_{3}\) (B) \(\mathrm{Cu}+\) conc \(\mathrm{HNO}_{3}\) (C) \(\mathrm{Zn}+\operatorname{dil} \mathrm{HNO}_{3}\) (D) \(\mathrm{Zn}+\mathrm{conc} \mathrm{HNO}_{3}\) Column II (p) \(\mathrm{NO}\) (q) \(\mathrm{NO}_{2}\) (r) \(\mathrm{N}_{2} \mathrm{O}\) (s) \(\mathrm{Cu}\left(\mathrm{NO}_{3}\right)_{2}\) (t) \(\mathrm{Zn}\left(\mathrm{NO}_{3}\right)_{2}\)

Match the following, choosing one item from column \(\mathbf{X}\) and one from column Y. (i) \(\mathrm{Hg}_{2} \mathrm{Cl}_{2}\) (ii) \(\left(\mathrm{NaPO}_{3}\right)_{n}\) (iii) \(\mathrm{NO}_{3}^{-}\) (iv) \(\mathrm{SnO}_{2}\) (v) \(\quad \mathrm{KCl} . \mathrm{MgCl}_{2} \cdot 6 \mathrm{H}_{2} \mathrm{O}\) (vi) \(\mathrm{AgNO}_{3}\) \(\mathbf{X} \quad \mathbf{Y}\) (a) cassiterite (b) lunar caustic (c) producer gas (d) water softener (e) brown ring test (f) carnallite (vii) \(\mathrm{CO}+\mathrm{N}_{2}\) (g) calomel

For the following Assertion and Reason, the correct option is: Assertion: For hydrogenation reactions, the catalytic activity increases from Group 5 to Group 11 metals with maximum activity shown by Group \(7-9\) elements. Reason: The reactants are most strongly adsorbed on group \(7-9\) elements. (a) The assertion is true, but the reason is false. (b) Both assertion and reason are false. (c) Both assertion and reason are true and the reason is the correct explanation for the assertion. (d) Both assertion and reason are true but the reason is not the correct explanation for the assertion.

(i) Write the chemical reactions involved in the extraction of metallic silver from argentite. (ii) Write the balanced chemical equation for developing photographic films.

Compare qualitatively the first and second ionisation potentials of copper and zinc. Explain the observation.

Mention the products formed when zinc oxide is treated with excess of sodium hydroxide solution.

What happens when : (i) aqueous ammonia is added dropwise to a solution of copper sulphate till it is in excess. (ii) \(\mathrm{CrCl}_{3}\) solution is treated with sodium hydroxide and then with hydrogen peroxide.

Give reasons for the following : (i) \(\mathrm{CrO}_{3}\) is an acid anhydride. (ii) The species \(\left[\mathrm{CuCl}_{4}\right]^{2-}\) exists while \(\left[\mathrm{CuI}_{4}\right]^{2-}\) does not. (iii) The colour of mercurous chloride, \(\mathrm{Hg}_{2} \mathrm{Cl}_{2}\), changes from white to black when treated with ammonia. (iv) Zinc and not copper is used for the recovery of metallic silver from complex \(\left[\mathrm{Ag}(\mathrm{CN})_{2}\right]^{-}\). Explain. (v) Most transition metal compounds are coloured. (vi) Silver bromide is used in photography.

State with balanced equations, what happens when (i) Silver is treated with hot concentrated sulphuric acid. (ii) Ammonium dichromate is heated. (iii) Hydrogen sulphide is passed through a solution of potassium permanganate acidified with dilute sulphuric acid.

A white amorphous powder (A) on heating yields a colourless, noncombustible gas (B) and a solid (C). The latter compound assumes a yellow colour on heating and changes to white on cooling. ' \(C\) ' dissolves in dilute acid and the resulting solution gives a white precipitate on adding \(\mathrm{K}_{4}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]\) solution. A' dissolves in dilute HCl with the evolution of gas, which is identical in all respects with ' \(\mathrm{B}\) '. The gas 'B' turns lime water milky, but the milkiness disappears with the continuous passage of gas. The solution of ' \(A\) ', as obtained above, gives a white precipitate (D) on the addition of excess of \(\mathrm{NH}_{4} \mathrm{OH}\) and passing \(\mathrm{H}_{2} \mathrm{~S}\). Another portion of the solution gives initially a white precipitate (E) on the addition of sodium hydroxide solution, which dissolves on futher addition of the base. Identify the compounds \(\mathrm{A}, \mathrm{B}, \mathrm{D}\), and \(\mathrm{E}\).