Chapter 19

Among which of the following pairs of ions, the lower oxidation state in aqueous solution is more stable than the other? (a) \(\mathrm{Ti}^{+}, \mathrm{Ti}^{3+}\) (b) \(\mathrm{V}^{2+}, \mathrm{VO}^{2+}\) (c) \(\mathrm{Cr}^{2+}, \mathrm{Cr}^{3+}\) (d) \(\mathrm{Cu}^{+}, \mathrm{Cu}^{2+}\)

Which of these ions is coloured as well as paramagnetic in nature? (a) \(\mathrm{Cu}^{2+}\) (b) \(\mathrm{Cu}^{+}\) (c) \(\mathrm{Nl}^{2+}\) (d) Both a and c

The aqueous solution containing which one of the following ions will be colourless? (a) \(\mathrm{Sc}^{3+}\) (b) \(\mathrm{Fe}^{3+}\) (c) \(\mathrm{Fe}^{2+}\) (d) \(\mathrm{Mn}^{2+}\)

Which of the following is a highly corrosive salt? (a) \(\mathrm{FeCl}_{2}\) (b) \(\mathrm{HgCl}_{2}\) (c) \(\mathrm{PbCl}_{2}\) (d) \(\mathrm{Hg}_{2} \mathrm{Cl}_{2}\)

A complex compound of \(\mathrm{Co}^{3+}\) with molecular formula \(\mathrm{CoCl}_{\mathrm{x}} \cdot \mathrm{yNH}_{3}\) gives a total of 3 ions when dissolved in water. How many Cl- ions satisfy both primary as well as the secondary valencies in this complex? (a) 3 (b) 1 (c) 4 (d) zero

In which of the following metal complex, does the central metal atom have zero Oxidation state? (a) \(\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{SO}_{4}\) (b) \(\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]\) (c) \(\left[\mathrm{Ni}(\mathrm{CO})_{4}\right]\) (d) \(\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{2} \mathrm{Cl}_{2}\right]\)

Misch metal is (a) an alloy of copper (b) an alloy of lanthanoid metal (c) an alloy of aluminium (d) a mixture of chromium and lead chromate

Which of the following pairs of ions is colourless? (a) \(\mathrm{Ti}^{3+}, \mathrm{Cu}^{2+}\) (b) \(\mathrm{Sc}^{3+}, \mathrm{Zn}^{2+}\) (c) \(\mathrm{Co}^{2+}, \mathrm{Fe}^{3+}\) (d) \(\mathrm{Ni}^{2+}, \mathrm{V}^{3+}\)

Which of the following pairs of ions have same paramagnetic moment? (a) \(\mathrm{Cu}^{2+}, \mathrm{Ti}^{-3+}\) (b) \(\mathrm{Ti}^{-3+}, \mathrm{Ni}^{2+}\) (c) \(\mathrm{Ti}^{4+}, \mathrm{Cu}^{2+}\) (d) \(\mathrm{Mn}^{2+}, \mathrm{Cu}^{2+}\)

Lanthanides and actinides resemble each other in (a) oxidation state (b) ionization energy (c) formation of complexes (d) electron configuration

Among the following series of transition metal ions, the one where all metal ions have \(3 \mathrm{~d}^{2}\) electronic configuration is (a) \(\mathrm{Ti}^{+}, \mathrm{V}^{4+}, \mathrm{Cr}^{6+}, \mathrm{Mn}^{7+}\) (b) \(\mathrm{Ti}^{2+}, \mathrm{V}^{3+}, \mathrm{Cr}^{4+}, \mathrm{Mn}^{3+}\) (c) \(\mathrm{Ti}^{3+}, \mathrm{V}^{2+}, \mathrm{Cr}^{3+}, \mathrm{Mn}^{4+}\) (d) \(\mathrm{Ti}^{4+}, \mathrm{V}^{3+}, \mathrm{Cr}^{2+}, \mathrm{Mn}^{3+}\)

Which of the following are coloured due to charge transfer spectra (a) \(\mathrm{CrO}_{3}\) (b) \(\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right) \mathrm{NO}\right] \mathrm{SO}_{4}\) (c) \(\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\) (d) All of these

How many electrons are involved in the oxidation by \(\mathrm{KMnO}_{4}\) in basic medium? (a) 5 (b) 3 (c) 2 (d) 1

For which lanthanide are \(+2\) and \(+3\) oxidation states are common? (a) Eu (b) \(\mathrm{Na}\) (c) \(\mathrm{Ce}\) (d) \(\mathrm{La}\)

An alkaline solution of and citrate ions is called (a) silver chloride; Tollen's reagent (b) cupric sulphate; Benedict's solution (c) silver nitrate; Fehling's solution (d) cupric sulphate; Schiff's reagents

Ferrous ion changes to X ion, on reacting with acidified hydrogen peroxide. The number of d-electrons present in \(\mathrm{X}\) and its magnetic moment (in B.M.) are respectively (a) 5 and \(4.9\) (b) 4 and \(5.92\) (c) 6 and \(6.95\) (d) 5 and \(5.92\)

Which one of the following characteristics of the transition metal is associated with their catalytic activity? (a) variable oxidation states (b) colour of hydrated ions (c) paramagnetic behaviour (d) high enthalpy of atomization

Iron loses its magnetic property at (a) melting point (b) curie point (c) \(1000 \mathrm{~K}\) (d) boiling point

In the extraction of zinc, the formation of blue flame is due to the burning of (a) \(\bar{C}\) (b) \(\mathrm{CO}\) (c) \(\mathrm{Zn}\) (d) \(\mathrm{ZnO}\)

Which one of the following ions exhibits colour in aqueous solution? (a) \(\mathrm{Ti}^{4+}\) (b) \(\mathrm{Zn}^{2+}\) (c) \(\mathrm{Ni}^{2+}\) (d) \(\mathrm{Sc}^{3+}\)

The number of un-paired electrons in \(\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{5} \mathrm{NO}\right]\) \(\mathrm{SO}_{4}\) (a) 1 (b) 2 (c) 3 (d) 4

Which one of the following ions is colourless in its aqueous solution? (a) \(\mathrm{Ti}^{3+}\) (b) \(\mathrm{Cu}^{2+}\) (c) \(\mathrm{Ni}^{2+}\) (d) \(\mathrm{Zn}^{2+}\)

Which one of the following ions exhibit highest magnetic moment? (a) \(\mathrm{Cu}^{2+}\) (b) \(\mathrm{Ti}^{3+}\) (c) \(\mathrm{Ni}^{2+}\) (d) \(\mathrm{Mn}^{2+}\)

Which one of the following is a diamagnetic ion? (a) \(\mathrm{Cu}^{2+}\) (b) \(\mathrm{Mn}^{2+}\) (c) \(\mathrm{Sc}^{3+}\) (d) \(\mathrm{Co}^{2+}\)

Which one of the following pairs of ions has the same electronic configuration? (a) \(\mathrm{Cr}^{3+}, \mathrm{Fe}^{3+}\) (b) \(\mathrm{Fe}^{3+}, \mathrm{Mn}^{2+}\) (c) \(\mathrm{Fe}^{5+}, \mathrm{Co}^{3+}\) (d) \(\mathrm{Sc}^{3+}, \mathrm{Cr}^{3+}\)

Iron sulphide is heated in air to form 'A', an oxide of sulphur. 'A' is dissolved in water to give an acid. The basicity of this acid is (a) zero (b) 1 (c) 2 (d) 3

Stainless steel vessels are made from steel containing (a) \(\mathrm{W}\) (b) \(\mathrm{Mn}\) (c) \(\mathrm{Cr}\) (d) \(\mathrm{Ni}\)

Which of the following reacts with concentrated sulphuric acid? (a) \(\mathrm{Pb}\) (b) \(\mathrm{Pt}\) (c) \(\mathrm{Ag}\) (d) \(\mathrm{Au}\)

The number of moles of \(\mathrm{AgCl}\) precipitated when excess \(\mathrm{AgNO}_{3}\) is added to one mole of \(\left[\mathrm{Cr}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{Cl}_{2}\right]\) \(\mathrm{Cl}\) is (a) \(3.0\) (b) \(2.0\) (c) \(1.0\) (d) zero

The element that can exhibit the highest number of oxidation states amongst the following is (a) \(\mathrm{Mn}\) (b) \(\mathrm{CO}\) (c) \(\mathrm{V}\) (d) \(\mathrm{Ni}\)

The oxidation number of cobalt in \(\mathrm{K}_{3}\left[\mathrm{Co}\left(\mathrm{NO}_{2}\right)_{6}\right]\) is (a) \(-3\) (b) \(+3\) (c) \(-4\) (d) \(+4\)

Which of the following is not correctly matched. List I List II (a) \(\mathrm{Cu}_{2} \mathrm{O}\) Red (b) \(\mathrm{Cu}_{2} \mathrm{I}_{2}\) Blue (c) \(\mathrm{Fe}_{4}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]_{3}\) Blue (d) \(\mathrm{CuO}\) Black

If \(\mathrm{NaOH}\) is added to an aqueous solution of zinc ions, a white precipitate appears and on adding excess of \(\mathrm{NaOH}\), the precipitate dissolves. In this solution, zinc exists in the (a) anionic part (b) cationic part (c) both in cationic and anionic parts (d) there is no zinc in the solution

The black compound formed during the reaction between sodium thiosulphate and silver nitrate is (a) silver sulphite \(\left(\mathrm{Ag}_{2} \mathrm{SO}_{3}\right)\) (b) silver sulphate \(\left(\mathrm{Ag}_{2} \mathrm{SO}_{4}\right)\) (c) silver sulphide \(\left(\mathrm{Ag}_{2} \mathrm{~S}\right)\) (d) silver thiosulphate \(\left(\mathrm{Ag}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\right)\)

Zn gives \(\mathrm{H}_{2}\) gas with \(\mathrm{H}_{2} \mathrm{SO}_{4}\) and \(\mathrm{HCl}\) but not with \(\mathrm{HNO}_{3}\) because (a) in electrochemical series \(\mathrm{Zn}\) is above hydrogen (b) \(\mathrm{NO}_{3}^{-}\)ion is reduced in preference to hydronium ion (c) \(\mathrm{Zn}\) acts as an oxidizing agent when reacts with \(\mathrm{HNO}_{3}\) (d) \(\mathrm{HNO}_{3}\) is weaker acid than \(\mathrm{H}_{2} \mathrm{SO}_{4}\) and \(\mathrm{HCl}\)

Which of the following is obtained when Fe reacts with dilute \(\mathrm{HNO}_{3}\) ? (a) NO (b) \(\mathrm{N}_{2} \mathrm{O}\) (c) \(\mathrm{NO}_{2}\) (d) none of these

The correct order of ionic radii of \(\mathrm{Y}^{3+}, \mathrm{La}^{3+}, \mathrm{Eu}^{3+}\) and \(\mathrm{Lu}^{3+}\) is (a) \(\mathrm{Lu}^{3+}<\mathrm{Eu}^{3+}<\mathrm{La}^{3+}<\mathrm{Y}^{3+}\) (b) \(\mathrm{La}^{3+}<\mathrm{Eu}^{3+}<\mathrm{Lu}^{3+}<\mathrm{Y}^{3+}\) (c) \(\mathrm{Y}^{3+}<\mathrm{La}^{3+}<\mathrm{Eu}^{3+}<\mathrm{Lu}^{3+}\) (d) \(\mathrm{Y}^{3+}<\mathrm{Lu}^{3+}<\mathrm{Eu}^{3+}<\mathrm{La}^{3+}\)

Two stable ions of first transition series which have the largest number of unpaired electrons and have the highest magnetic moment are (a) \(\mathrm{Ni}^{2+}\) and \(\mathrm{Co}^{2+}\) (b) \(\mathrm{Cr}^{3+}\) and \(\mathrm{Fe}^{2+}\) (c) \(\mathrm{Fe}^{3+}\) and \(\mathrm{Mn}^{2+}\) (d) \(\mathrm{Ti}^{4+}\) and \(\mathrm{Cr}^{3+}\)

What is the general outer configuration of the coinage metals? (a) \(\mathrm{ns}^{2} \mathrm{np}^{6}\) (b) \((\mathrm{n}-1) \mathrm{d}^{9} \mathrm{~ns}^{2}\) (c) \((\mathrm{n}-1) \mathrm{d}^{10} \mathrm{~ns}^{1}\) (d) \((\mathrm{n}-1) \mathrm{d}^{10} \mathrm{~ns}^{2}\)

In the equation \(4 \mathrm{M}+8 \mathrm{CN}^{-}+2 \mathrm{H}_{2} \mathrm{O}+\mathrm{O}_{2} \longrightarrow 4\left[\mathrm{M}(\mathrm{CN})_{2}\right]^{-}+\) \(4 \mathrm{OH}^{-}\) identify the metal \(\mathrm{M}\). (a) zinc (b) iron (c) copper (d) silver

Lanthanoides are (a) 14 elements in the VI period (atomic number \(=58\) to 71) that are filling the \(4 \mathrm{f}\)-sublevel (b) 14 elements in the VII period (atomic number = 50 to 71 ) that are filling the \(4 \mathrm{f}\)-sublevel (c) 14 elements in the VII period (atomic number = 90 to 103 ) that are filling the 5 f-sublevel (d) 14 elements in the VI period (atomic number \(=90\) to 103 ) that are filling the 4 f-sublevel

Which of the following compound is both paramagnetic and coloured? (a) \(\left(\mathrm{NH}_{4}\right)_{2}\left[\mathrm{TiCl}_{6}\right]\) (b) \(\mathrm{VOSO}_{4}\) (c) \(\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7}\) (d) \(\mathrm{K}_{3}\left[\mathrm{Cu}(\mathrm{CN})_{4}\right]\)

Gold is extracted by hydrometallurgical process, based on its property (a) of being electropositive (b) of being less reactive (c) to form complexes which are soluble (d) to form salts which are water soluble

A pair of amophoteric oxides from the following is (a) \(\mathrm{VO}_{2}\) and \(\mathrm{CrO}\) (b) \(\mathrm{VO}_{2}\) and \(\mathrm{CrO}_{3}\) (c) \(\mathrm{VO}\) and \(\mathrm{V}_{2} \mathrm{O}_{5}\) (d) \(\mathrm{VO}_{2}\) and \(\mathrm{Cr}_{2} \mathrm{O}_{3}\)

Corrosion of iron is essentially an electro-chemical phenomenon, where the cell reactions are (a) \(\mathrm{Fe}\) is oxidized to \(\mathrm{Fe}^{2+}\) and dissolved oxygen in water is reduced to \(\mathrm{OH}\) (b) Fe is oxidized to \(\mathrm{Fe}^{3+}\) and \(\mathrm{H}_{2} \mathrm{O}\) is reduced to \(\mathrm{O}_{2}^{2-}\) (c) Fe is oxidized to \(\mathrm{Fe}^{2+}\) and \(\mathrm{H}_{2} \mathrm{O}\) is reduced to \(\mathrm{O}_{2}\) (d) Fe is oxidized to \(\mathrm{Fe}^{2+}\) and \(\mathrm{H}_{2} \mathrm{O}\) is reduced to \(\mathrm{O}_{2}\)

If the spin only magnetic moment of \(\mathrm{Cu}^{2+}\) is \(1.73 \mathrm{BM}\), then the number of unpaired electron's present are (a) 2 (b) 3 (c) 0 (d) 1

Identify the correct order in which the covalent radius of the following elements increases 1\. Ti 2\. \(\mathrm{Ca}\) 3\. \(\mathrm{Sc}\) (a) \(3,2,1\) (b) \(2,1,3\) (c) \(1,3,2\) (d) \(1,2,3\)

What is the current order of spin only magnetic moment (in B.M.) of \(\mathrm{Mn}^{2+}, \mathrm{Cr}^{2+}\) and \(\mathrm{V}^{2+\text { ? }}\) (a) \(\mathrm{Mn}^{2+}>\mathrm{V}^{2+}>\mathrm{Cr}^{2+}\) (b) \(\mathrm{V}^{2+}>\mathrm{Cr}^{2+}>\mathrm{Mn}^{2+}\) (c) \(\mathrm{Mn}^{2+}>\mathrm{Cr}^{2+}>\mathrm{V}^{2+}\) (d) \(\mathrm{Cr}^{2+}>\mathrm{V}^{2+}>\mathrm{Mn}^{2+}\)

Which statement is not correct with respect to transition metals? (a) the colour of the hydrated ions is due to transitions of electrons from different 'd' orbitals of the same principal quantum number (b) most transition metals should, on thermodynamic considerations, liberate hydrogen from acids (c) the complex formation of transition metal ions is often accompanied by a change of colour and sometimes by a change in the intensity of the colour (d) the compounds of the elements in low oxidation states are generally ionic

Which of the following statements is not correct? (a) in oxyhaemoglobin, \(\mathrm{Fe}^{2+}\) is paramagnetic. (b) during respiration, the size of \(\mathrm{Fe}^{2+}\) increases when it changes from diamagnetic to paramagnetic state. (c) four heme groups are present in haemoglobin. (d) heme is the prosthetic group and it is non protein part of haemoglobin.