CBSE Questions for Class 12 Engineering Chemistry The D-And F-Block Elements Quiz 3 - MCQExams.com

The properties of $$Zr$$ and $$Hf$$ are same because
  • they have similar radii
  • they belong to d-b;ock
  • they have same valence electrons
  • None of the above
In  $$Cr_2O^{2-}_7$$ every Cr is linked to :
  • two O atoms
  • three O atoms
  • four O atoms
  • five O atoms
Which one of the following is expected to be paramagnetic complex?
  • $$[Ni(H_2O)_6]^{2+}$$
  • $$[Ni(CO)_4]$$
  • $$[Zn(NH_3)_4]^{2+}$$
  • $$[Co(NH_3)_6]^{3+}$$
$$ [Sc(H_2O)_6]^{3+} $$ ion is 
  • colourless and diamagnetic
  • coloured and octahedral
  • colourless and paramagnetic
  • coloured and paramagnetic
Which of the following statement is not true? 
  • Colourless compounds of transition elements are paramagnetic
  • Coloured compounds of transition elements are paramagnetic
  • Colourless compounds of transition elements are diamagnetic
  • Transition elements form the complex compounds
Wilkinson's catalyst is used in
  • polymerization
  • condensation
  • halogenation
  • hydrogenation
Following elements do not show the properties characteristic of d-block elements :
  • $$Cu, Ag, Au$$
  • $$Zn, Hg, Cd$$
  • $$Sc, Ti, V$$
  • $$Fe, Co, Ni$$
Transitional elements exhibit variable valencies because they release electrons from the following orbits :
  • $$ns $$ orbit
  • $$ns$$ and $$ np  $$ orbits
  • $$(n-1)d$$ and $$ns$$ orbits
  • $$(n-1)d$$ orbit
The total spin and magnetic moment for the atom with atomic number 25 are respectively________________
  • $$\pm$$3, $$\sqrt{48}$$ BM
  • $$\pm$$3, $$\sqrt{35}$$ BM
  • $$\pm$$$$\frac{3}{2}$$, $$\sqrt{48}$$ BM
  • $$\pm$$$$\frac{5}{2}$$, $$\sqrt{35}$$ BM
Which of the following pairs of elements have almost similar atomic radii?
  • $$Zr, Hf$$
  • $$Mo, W$$
  • $$Co, Ni$$
  • $$An, Pb$$
Which one is false in the following statement
  • A catalyst is specific in its action
  • A very small amount of the catalyst alters the rate of a reaction
  • The number of free valencies on the surface of the catalyst increases on subdivision
  • Ni is used as catalyst in the manufacture of ammonia in the redox reaction
The transition metal ions responsible for color in Ruby and Emerald are, respectively :
  • $${Co}^{3+}$$ and $${Cr}^{3+}$$
  • $${Co}^{3+}$$ and $${Co}^{3+}$$
  • $${Cr}^{3+}$$ and $${Cr}^{3+}$$
  • $${Cr}^{3+}$$ and $${Co}^{3+}$$
The correct order of spin-only magnetic moments among the following is:

(Atomic number: $$Mn=25, Co=27, Ni=28, Zn=30)$$.
  • $$[ZnCl_4]^{2-} > [NiCl_4]^{2-} > [CoCl_4]^{2-} > [MnCl_4]^{2-}$$
  • $$[CoCl_4]^{2-} > [MnCl_4]^{2-} > [NiCl_4]^{2-} > [ZnCl_4]^{2-}$$
  • $$[NiCl_4]^{2-} > [CoCl_4]^{2-} > [MnCl_4]^{2-} > [ZnCl_4]^{2-}$$
  • $$[MnCl_4]^{2-} > [CoCl_4]^{2-} > [NiCl_4]^{2-} > [ZnCl_4]^{2-}$$
The correct order of the spin-only magnetic moment of metal ions in the following low spin complexes, $$[V(CN)_6]^{4-}, [Fe(CN)_6]^{4-}$$, $$[Ru(NH_3)_6]^{3+}, $$ and $$[Cr(NH)_3)_6]^{2+}$$, is:
  • $$V^{2+} > Cr^{2+} > Ru^{3+} > Fe^{2+}$$
  • $$V^{2+} > Ru^{3+} > Cr^{2+} > Fe^{2+}$$
  • $$Cr^{2+} > V^{2+} > Ru^{3+} > Fe^{2+}$$
  • $$Cr^{2+} > Ru^{3+} > Fe^{2+} > V^{2+}$$
Which one of the following does not correctly represent the correct order of the property indicated against it?
  • $${Ti}^{3+}< {V}^{3+}< {Cr}^{3+}< {Mn}^{3+}$$; increasing magnetic moment
  • $$Ti< V< Cr< Mn$$; increasing melting point
  • $$Ti< V< Mn< Cr$$; increasing 2nd ionization enthalpy
  • $$Ti< V< Cr< Mn$$; increasing number of oxidation states
Which one of the following ions exhibits d-d transition and paramagnetism as well?
  • $$MnO_{4}^{-}$$
  • $$CrO_{4}^{2-}$$
  • $$MnO_{4}^{2-}$$
  • $$Cr_{2}O_{7}^{2-}$$
Match the metal ions given in Column I with the spin magnetic moments of the ions given in Column II and assign the correct code :

Column I
Column II
a.$$Co^{3+}$$i.$$\sqrt {8}B.M.$$
b.$$Cr^{3+}$$ii.$$\sqrt {35}B.M.$$
c.$$Fe^{3+}$$iii.$$\sqrt {3}B.M.$$
d.$$Ni^{2+}$$iv.$$\sqrt {24}B.M.$$
v.$$\sqrt {15}B.M.$$
  • $$a - iv, b - i, c - ii, d - iii$$
  • $$a - iv, b - v, c - ii, d - i$$
  • $$a - iii, b - v, c - i, d - ii$$
  • $$a - i, b - ii, c - iii, d - iv$$
Which of the following arrangements does not represent the correct order of the property stated against it?
  • $${ V }^{ 2+ }<{ Cr }^{ 2+ }<{ Mn }^{ 2+ }<{ Fe }^{ 2+ }$$: Paramagnetic behavior
  • $${ Ni }^{ 2+ }<{ Co }^{ 2+ }<{ Fe }^{ 2+ }<{ Mn }^{ 2+ }$$: Ionic size
  • $${ Co }^{ 3+ }<{ Fe }^{ 3+ }<{ Cr }^{ 3+ }<{ Sc }^{ 3+ }$$: Stability in aqueous solution
  • $$Sc< Ti< Cr< Mn$$: Number of oxidation states
Which of the following has the highest paramagnetism? 
  • $$[Cr(H_2O)_6]^{3+}$$
  • $$[Fe(H_2O)_6]^{2+}$$
  • $$[Cu(H_2O)_6]^{2+}$$
  • $$[Zn(H_2O)_6]^{2+}$$
The color of $$Co{ Cl }_{ 3 }.5{ NH }_{ 3 }.{ H }_{ 2 }O$$ is:
  • red
  • orange
  • orange-yellow
  • pink
Which of the following transition metal ions will have definite value of magnetic moment?
  • $$Sc^{3+}$$
  • $$Ti^{3+}$$
  • $$Cu^+$$
  • $$Zn^{2+}$$
Which of the following group belongs to actinide series ?
  • Th, Pa, U
  • Ce Pr, Nd
  • Ba, La, Hf
  • Pt, Au, Ag
The Lanthanide contraction relates to:
  • oxidation states
  • magnetic state
  • atomic radius
  • valence electrons

Which of the following has smallest ionic radius ?
  • Nd$$^{3+}$$
  • Dy$$^{3+}$$
  • Lu$$^{3+}$$
  • Pm$$^{3+}$$

The highest magnetic moment is shown by the transition metal ion with which of the following outermost electronic configuration? 
  • $$3d^{2}$$
  • $$3d^{5}$$
  • $$3d^{7}$$
  • $$3d^{9}$$

Which sub shell is filled up progressively in actinoids?
  • 4f
  • 5f
  • 6d
  • 7s

The Lanthanoid contraction refers to:
  • valence electrons of the Lanthanide series
  • ionic radius of the series
  • the density of the series
  • nuclear mass of the series

Which of the following elements belongs to actinide series?
  • Lu
  • Gd
  • Th
  • La

Which one of the following ionic species will impart colour to an aqueous solution?
  • Sc$$^{+3}$$
  • Cd$$^{+2}$$
  • Zn$$^{+2}$$
  • Cr$$^{+3}$$

The following is not a noble metal
  • Au
  • Cu
  • Ag
  • Pt
Which of the following is not an actinoid ?
  • Am
  • Cm
  • Fm
  • Tm

Potassium dichromate on heating does not gives :
  • $$O_2$$
  • $$Cr_2O_3$$
  • $$K_2O$$
  • $$K_2CrO_4$$
The correct statement for $$d$$-block element is:
  • It shows magnetic property
  • It has variable valency
  • It has tendency of formation of colored ions
  • It has complete $$d$$-orbitals
The highest magnetic moment is shown by the transition metal with the configuration:
  • $${3d}^{2}$$
  • $${3d}^{5}$$
  • $${3d}^{7}$$
  • $${3d}^{9}$$
5f series elements are known as_______
  • Lanthanides
  • Representative elements
  • Transition elements
  • Actinides

Platinum, palladium and iridium are called noble metals because:
  • Alfred Nobel discovered them
  • They are inert towards many common reagents
  • They are shining, lustrous and pleasing to look at
  • They are found in active state
The ion which shows maximum paramagnetic character among the bivalent ions of the first transition metal series is :
  • Co$$^{2+}$$
  • Cu$$^{2+}$$
  • Cr$$^{2+}$$
  • Fe$$^{2+}$$
  • Mn$$^{2+}$$
The first and last elements of actinides are:
  • Actinium and Thorium
  • Actinium and Nobelium
  • Actinium and Mendelevium
  • Actinium and Lawrencium

The purple colour of $$[Ti(H_{2}O)_{6}]^{3+}$$ ions is due to ______________?
  • unpaired d-electron
  • charge transfer
  • intermolecular vibrations
  • presence of paired electrons
Transition metals show paramagnetism due to 
  • Characteristic configuration
  • high lattice energy
  • variable oxidation states
  • unpaired electrons
Why are the compounds of transition metal generally coloured ?
  • due to s being filled before d (Aufbau principle)
  • Due to presence of unpaired electron
  • unfilled d orbital
  • d-d transition
The catalytic activity of the transition metals and their compounds is ascribed to their
  • Chemical reactivity
  • Magnetic behaviour
  • Unfilled d-orbitals
  • Ability to adopt multiple oxidation states and their complexing ability
Gallium is in __________ state at room temperature.
  • plasma
  • liquid
  • solid
  • gaseous

Which of the following statement is not correct?
  • $$La(OH)_3$$, is less basic than $$Lu(OH)_3$$
  • In lanthanide series, ionic radius of $$Ln^3+$$ ions decreases
  • $$La$$ is actually an element of transition series rather than lanthanide series
  • Atomic radii of $$Zr$$ and $$Hf$$ are same because of lanthanide contraction
Statement 1: Transition metal compounds are often colored.
Statement 2: They frequently possess partially filled d-orbitals.
  • Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1.
  • Both the Statement 1 and Statement 2 are correct, but Statement 2 is NOT the correct explanation of Statement 1.
  • Statement 1 is correct, but Statement 2 is not correct.
  • Statement 1 is not correct, but Statement 2 is correct.
Monazite is an ore of:
  • titanium
  • throium
  • zirconium
  • iron
Chromium - plated steel is a material of popular use. During its process of manufacture, the effluent contains chromate and cyanide ions as impurities. After these are chemically removed, carbon dioxide and salt (sodium chloride) still remain as impurities. This salt solution is purified electrolytically by adding carbonaceous matter which acts as:
  • a microcell
  • an electrode
  • a cathode
  • a salt absorber
Titanium oxide is added in interior paints for walls of rooms, halls and galleries to give :
  • a whiter 'white'
  • a greener 'green'
  • a redder 'red'
  • silver-white
It is sometimes necessary to remove colouring matter contained as an impurity in glass. Glass is decolourised by:
  • wood charcoal
  • manganese dioxide
  • bleaching powder
  • hydrogen
Lanthanides and actinides resemble in:
  • electronic configuration
  • oxidation state
  • ionization energy
  • formation of complexes
0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 12 Engineering Chemistry Quiz Questions and Answers