Q.1 Which of the following elements is considered a typical transition element?
Calcium (Ca)
Titanium (Ti)
Sodium (Na)
Aluminium (Al)
Explanation - Titanium is a d-block element with partially filled d-orbitals in its stable oxidation state, making it a typical transition element.
Correct answer is: Titanium (Ti)
Q.2 The general electronic configuration of the first-row transition elements is:
[Ar] 3d^1-10 4s^1-2
[Kr] 4d^1-10 5s^1-2
[Ne] 3s^1-2 3p^1-6
[Xe] 4f^1-14 5d^1-10 6s^1-2
Explanation - First-row transition elements have electrons filling the 3d subshell after the 4s subshell, giving the general configuration [Ar] 3d^1-10 4s^1-2.
Correct answer is: [Ar] 3d^1-10 4s^1-2
Q.3 Which of the following transition metals commonly exhibits variable oxidation states?
Zinc (Zn)
Scandium (Sc)
Iron (Fe)
Cadmium (Cd)
Explanation - Iron exhibits multiple oxidation states, primarily +2 and +3, which is characteristic of transition elements.
Correct answer is: Iron (Fe)
Q.4 Which of the following ions is colored due to d-d transitions?
Zn^2+
Ti^3+
Na+
Mg^2+
Explanation - Ti^3+ has one electron in the d-orbital, which can undergo d-d transitions when light is absorbed, producing color.
Correct answer is: Ti^3+
Q.5 Which property is NOT generally associated with transition elements?
Formation of colored compounds
Variable oxidation states
Low melting points
Paramagnetism
Explanation - Transition elements usually have high melting points due to metallic bonding and partially filled d-orbitals.
Correct answer is: Low melting points
Q.6 Which transition metal forms a +2 oxidation state but not a +3 state commonly?
Zinc (Zn)
Copper (Cu)
Manganese (Mn)
Iron (Fe)
Explanation - Zinc predominantly exhibits the +2 oxidation state as it has a fully filled d^10 configuration and cannot easily form +3.
Correct answer is: Zinc (Zn)
Q.7 Which element shows the highest magnetic moment among the first-row transition metals?
Mn^2+
Fe^2+
Ni^2+
Cu^2+
Explanation - Mn^2+ has five unpaired electrons in its d-orbital, giving the highest magnetic moment.
Correct answer is: Mn^2+
Q.8 Which of the following transition metals does not exhibit paramagnetism?
Copper (Cu^2+)
Zinc (Zn^2+)
Chromium (Cr^3+)
Iron (Fe^3+)
Explanation - Zn^2+ has a d^10 configuration with no unpaired electrons, making it diamagnetic, not paramagnetic.
Correct answer is: Zinc (Zn^2+)
Q.9 The formation of complex ions is a characteristic feature of transition elements due to:
Partially filled s-orbitals
Fully filled p-orbitals
Partially filled d-orbitals
High ionization energy
Explanation - Partially filled d-orbitals allow transition metals to form coordinate bonds with ligands, forming complex ions.
Correct answer is: Partially filled d-orbitals
Q.10 Which transition metal is most commonly associated with catalysis in the Haber process?
Iron (Fe)
Copper (Cu)
Titanium (Ti)
Zinc (Zn)
Explanation - Iron acts as a catalyst in the Haber process to synthesize ammonia from nitrogen and hydrogen.
Correct answer is: Iron (Fe)
Q.11 Which of the following transition elements has a completely filled d-orbital in its common oxidation state?
Zinc (Zn^2+)
Titanium (Ti^3+)
Iron (Fe^3+)
Copper (Cu^2+)
Explanation - Zn^2+ has a d^10 configuration in its +2 oxidation state, meaning its d-orbitals are completely filled.
Correct answer is: Zinc (Zn^2+)
Q.12 Which of the following is the electronic configuration of Cr^3+?
[Ar] 3d^3
[Ar] 3d^4
[Ar] 3d^5
[Ar] 3d^2
Explanation - Chromium loses three electrons (two from 4s and one from 3d) to form Cr^3+, leaving 3 electrons in the 3d subshell.
Correct answer is: [Ar] 3d^3
Q.13 Which of the following properties increases across the first-row transition series?
Atomic radius
Ionization energy
Reactivity with water
Number of oxidation states
Explanation - Ionization energy generally increases across the period due to increasing nuclear charge and decreasing atomic size.
Correct answer is: Ionization energy
Q.14 Which transition metal exhibits the +6 oxidation state most commonly?
Chromium (Cr)
Manganese (Mn)
Iron (Fe)
Copper (Cu)
Explanation - Chromium commonly exhibits +6 oxidation state in compounds like CrO_3 and chromates.
Correct answer is: Chromium (Cr)
Q.15 Which of the following elements is classified as a second-row transition element?
Zirconium (Zr)
Titanium (Ti)
Vanadium (V)
Chromium (Cr)
Explanation - Zirconium belongs to the 4d series, which is the second row of transition elements.
Correct answer is: Zirconium (Zr)
Q.16 Which of the following transition metals is most widely used in electroplating due to its resistance to corrosion?
Nickel (Ni)
Titanium (Ti)
Iron (Fe)
Manganese (Mn)
Explanation - Nickel is resistant to corrosion and is commonly used for electroplating metals.
Correct answer is: Nickel (Ni)
Q.17 Which transition metal ion forms a green-colored solution in aqueous medium?
Ni^2+
Cu^2+
Cr^3+
Mn^2+
Explanation - Cr^3+ in aqueous solution forms [Cr(H2O)6]^3+ which exhibits a green color due to d-d transitions.
Correct answer is: Cr^3+
Q.18 Which transition element has the highest density among the first-row elements?
Iron (Fe)
Copper (Cu)
Nickel (Ni)
Zinc (Zn)
Explanation - Copper has the highest density among the first-row transition elements due to its atomic mass and packing in the crystal lattice.
Correct answer is: Copper (Cu)
Q.19 Which transition metal is commonly used as a catalyst in the hydrogenation of vegetable oils?
Nickel (Ni)
Iron (Fe)
Copper (Cu)
Titanium (Ti)
Explanation - Nickel is used as a catalyst in hydrogenation reactions to convert unsaturated fats to saturated fats.
Correct answer is: Nickel (Ni)
Q.20 Which of the following is not a property of transition metals?
Formation of alloys
High electrical conductivity
Highly reactive with water
Catalytic activity
Explanation - Transition metals are generally less reactive with water compared to alkali metals.
Correct answer is: Highly reactive with water
Q.21 Which element shows the largest number of oxidation states among the first-row transition elements?
Manganese (Mn)
Iron (Fe)
Chromium (Cr)
Copper (Cu)
Explanation - Manganese exhibits oxidation states from +2 to +7, the largest among first-row transition elements.
Correct answer is: Manganese (Mn)
Q.22 Which transition element forms a colored oxide that is used in pigments?
Chromium (Cr)
Zinc (Zn)
Titanium (Ti)
Copper (Cu)
Explanation - Chromium oxides like Cr2O3 are used as green pigments due to their intense color from d-d transitions.
Correct answer is: Chromium (Cr)
Q.23 Which of the following first-row transition metals is least reactive chemically?
Copper (Cu)
Manganese (Mn)
Iron (Fe)
Chromium (Cr)
Explanation - Copper is relatively inert due to its filled d-orbitals and does not react easily with acids or water.
Correct answer is: Copper (Cu)
Q.24 Which of the following elements is used in making stainless steel?
Chromium (Cr)
Copper (Cu)
Nickel (Ni)
Manganese (Mn)
Explanation - Chromium is added to steel to make stainless steel because it forms a passive oxide layer preventing corrosion.
Correct answer is: Chromium (Cr)
Q.25 The ability of transition metals to form alloys is due to:
Similar atomic radii
Similar electronegativities
Delocalized d-electrons
High ionization energies
Explanation - Delocalized d-electrons allow transition metals to bond with each other, facilitating alloy formation.
Correct answer is: Delocalized d-electrons