JEE Chemistry The D and F Block Elements MCQs Set A

Question: The transition elements have a general electronic configuration

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Correct electronic configuration of Cr (Z = 24) is

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question:  Which of the following configuration is correct for iron ?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which one of the following ions has electronic configuration [Ar] 3d⁶

• a) Co³⁺
• b) Mn³⁺
• c) Ni³⁺
• d) Fe³⁺

Answer: Co³⁺

Question: Which of the following element does not belong to first transition series?

• a) Ag
• b) Fe
• c) V
• d) Cu

Answer: Ag

Question:

• a) Zn, Cd, Hg
• b) Fe, Co, Ni
• c) Cu, Ag, Au
• d) Se, Y, La

Answer: Zn, Cd, Hg

Question: The last electron in d-block elements goes to

• a) (n-1) d
• b) np
• c) nd
• d) (n-1) s

Answer: (n-1) d

Question: The elements which exhibit both vertical and horizontal similarites are

• a) transition elements
• b) representative elements
• c) inert gas elements
• d) rare elements

Answer: transition elements

Question:

• a) Fifth
• b) Second
• c) Fifteenth
• d) Third

Answer: Fifth

Question: In 3d-series atomic number (Z) varies from

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The valence shell of transition elements consists of

• a) (n-1) d ns orbitals
• b) (n-1) d orbitals
• c) nd orbitals
• d) ns np nd orbitals

Answer: (n-1) d ns orbitals

Question: Number of unpaired electrons in Ni²⁺(Z=28) is

• a) 2
• b) 8
• c) 4
• d) 6

Answer: 2

Question: Which of the following element is not a member of transition elements ?

• a) Ce
• b) Zn
• c) Pt
• d) Mo

Answer: Ce

Question: The number of unpaired electrons in gaseous species of Mn³⁺, Cr³⁺ and V³⁺ respectively are.

• a) 4, 3 and 2
• b) 4, 3 and 2
• c) 3, 3 and 2
• d) 3, 3 and 3

Answer: 4, 3 and 2

Question: The first element in the 3d-transition series is

• a) Sc
• b) V
• c) Ti
• d) Ca

Answer: Sc

Question: Which of the following has more unpaired d-electrons?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:

• a) 2
• b) 3
• c) 5
• d) 7

Answer: 2

Question: Which one of the following is an example of non-typical transition elements

• a) Zn, Cd, Hg
• b) Li, K, Na
• c) Be, Al, Pb
• d) Ba, Ga, Sr.

Answer: Zn, Cd, Hg

Question: Which of the following has the maximum number of unpaired electrons?

• a) Cr⁺
• b) Ti²⁺
• c) Fe²⁺
• d) Cu⁺

Answer: Cr⁺

Question:

• a) 5th period, group 11
• b) 5th period, group 4
• c) 4th period, group 5
• d) 6th period, group 9

Answer: 5th period, group 11

More Questions..................................

Question: Manganese belongs to

• a) 1st transition series
• b) 3rd transition series
• c) 2nd transition series
• d) 4th transition series

Answer: 1st transition series

Question: The no. of unpaired electrons in Mn⁷⁺ ions (At. no. of Mn = 25) is

• a) 0
• b) 2
• c) 2
• d) 3

Answer: 0

Question: Which one of the following species is paramagnetic?

• a) Co
• b) Zn
• c) Cu⁺
• d) N₂

Answer: Co

Question: Which of the following species is/are paramagnetic?

Fe²⁺, Zn⁰, Hg²⁺, Ti⁴⁺

• a) Fe²⁺ only
• b) Fe²⁺ and Hg²⁺
• c) Zn⁰ and Ti⁴⁺
• d) Zn⁰ and Hg²⁺

Answer: Fe²⁺ only

Question: In first transition series, the melting point of Mn is low because

• a) due to d⁵ configuration, metallic bonds are weak
• b) None of these
• c) due to d⁷ configuration, metallic bonds are weak
• d) due to d¹⁰ configuration, metallic bonds are strong

Answer: due to d⁵ configuration, metallic bonds are weak

Question: The transition metals have a less tendency to form ions due to

• a) All of these
• b) high heat of sublimation
• c) low heat of hydration of ions
• d) high ionisation energy

Answer: All of these

Question: The common oxidation states of Ti are

• a) + 2, + 3 and + 4
• b) + 3 and + 4
• c) + 2 and + 3
• d) – 3 and – 4

Answer: + 2, + 3 and + 4

Question:  Maximum oxidation state is shown by

• a) Os
• b) Co
• c) Mn
• d) Cr

Answer: Os

Question:  Which one of the elements with the following outer orbital configurations may exhibit the largest number of oxidation states?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which of the following pairs has the same size?

• a) Zr⁴⁺ , Hf ⁴⁺
• b) Fe²⁺ , Ni²⁺
• c) Zr⁴⁺ , Ti⁴⁺
• d) None of these

Answer: Zr⁴⁺ , Hf ⁴⁺

Question: For the four successive transition elements (Cr, Mn, Fe and Co), the stability of +2 oxidation state will be there in which of the following order?

• a) Mn > Fe > Cr > Co
• b) Co > Mn > Fe > Cr
• c) Fe > Mn > Co > Cr
• d) Cr > Mn > Co > Fe

Answer:  Mn > Fe > Cr > Co

Question: Iron exhibits +2 and + 3 oxidation states. Which of the following statements about iron is incorrect ?

• a) Ferrous compounds are more easily hydrolysed than the corresponding ferric compounds
• b) Ferrous compounds are less volatile than the corresponding ferric compounds
• c) Ferrous compounds are relatively more ionic than the corresponding ferric compounds
• d) Ferrous oxide is more basic in nature than the ferric oxide.

Answer: Ferrous compounds are more easily hydrolysed than the corresponding ferric compounds

Question: Four successive members of the first row transition elements are listed below with their atomic numbers. Which one of them is expected to have the highest third ionization enthalpy?

• a) Manganese (Z = 25)
• b) Vanadium (Z = 23)
• c) Chromium (Z = 24)
• d) Iron (Z = 26)

Answer: Manganese (Z = 25)

Question: Of the following outer electronic configurations of atoms, the highest oxidation state is achieved by which one of them

• a) (n – 1)d⁵ ns²
• b) (n – 1)d⁵ ns¹
• c) (n – 1)d³ ns²
• d) None of these

Answer: (n – 1)d⁵ ns²

Question: For d block elements the first ionization potential is of the order

• a) Zn > Fe > Cu > Cr
• b) Zn < Cu < Ni < Co
• c) Sc = Ti < V = Cr
• d) V > Cr > Mn > Fe

Answer: Zn > Fe > Cu > Cr

Question:  Which of the following does not represent the correct order of the properties indicated

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Zinc and mercury do not show variable valency like d-block elements because

• a) their d-shells are complete
• b) they are soft
• c) they have only two electrons in the outermost subshell
• d) their d-shells are incomplete

Answer: their d-shells are complete

Question: Which of the following transition element shows the highest oxidation state ?

• a) Mn
• b) V
• c) Fe
• d) Cr

Answer: Mn

Question: Which of the following elements does not showvariable oxidation states?

• a) Zinc
• b) Copper
• c) Iron
• d) Titanium

Answer: Zinc

Question: Which one of the following transition elements does not exhibit variable oxidation state?

• a) Sc
• b) Cu
• c) Ni
• d) Fe

Answer: Sc

Question: Electronic configuration of a transition element X in +3 oxidation state is [Ar]3d⁵. What is its atomic number ?

• a) 26
• b) 24
• c) 25
• d) 27

Answer: 26

Question:

• a) Cu
• b) Ni
• c) Fe
• d) Co

Answer: Cu

Question: Transition metals mostly are

• a) paramagnetic
• b) diamagnetic
• c) neither diamagnetic nor paramagnetic
• d) both diamagnetic and paramagnetic

Answer: paramagnetic

Question:  Transition metals usually exhibit highest oxidation states in their

• a) fluorides
• b) iodides
• c) chlorides
• d) bromides

Answer: fluorides

Question: Which of the following statements is incorrect?

• a)

  

• b) Zn, Cd and Hg have low m.p and are comparitively softer than other transition metals.
• c) Metals of 5d series forms strong metallic bonds as compared with metals of 3d series
• d) None of these

Answer: 

Question: Which of the following is incorrect?

• a) Mn shows oxidation state of +7 in MnF₇
• b) Fe and Co shows +3 oxidation state in FeX₃ and CoF₃
• c) V shows oxidation state of + 5 in VF₅.
• d) Cu does not shows +2 oxidation state with I–.

Answer: Mn shows oxidation state of +7 in MnF₇

Question: Which of the following is not correct about transition metals

• a) They do not exhibit variable valency
• b) They can form ionic or covalent compounds
• c) Their compounds are generally coloured
• d) Their melting and boiling points are high

Answer: They do not exhibit variable valency

Question: Transition elements

• a) exhibit variable oxidation states
• b) do not form coloured ions
• c) show inert pair effect
• d) have low melting point

Answer: exhibit variable oxidation states

Question: Which one of the following ions is the most stable in aqueous solution?

• a) Cr³⁺
• b) Ti³⁺
• c) V³⁺
• d) Mn³⁺

Answer: Cr³⁺

Question: Which one of the following does not correctly represent the correct order of the property indicated against it?

• a) Ti < V < Cr < Mn : increasing melting points
• b) Ti < V < Mn < Cr : increasing 2nd ionization enthalpy
• c) Ti < V < Cr < Mn : increasing number of oxidation states
• d) None of these

Answer: Ti < V < Cr < Mn : increasing melting points

Question: What is wrong about transition metals

• a) Diamagnetic
• b) Paramagnetic
• c) Form complexes
• d) Shows variable oxidation state

Answer: Diamagnetic

Question: Which of the following ions has the maximum magnetic moment?

• a) Mn⁺²
• b) Fe⁺²
• c) Cr^+2.
• d) None of these

Answer: Mn⁺²

Question:

• a) Co(Z = 27)
• b) Mn(Z = 25)
• c) Cr(Z = 24)
• d) Fe(Z = 26)

Answer: Co(Z = 27)

Question: Which one of the following ions exhibit highest magnetic moment?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:

• a) 3
• b) 4
• c) 2
• d) 5

Answer:  3

Question: Titanium shows magnetic moment of 1.73 B.M. in its compound. What is the oxidation number of Ti in the compound?

• a) +3
• b) +1
• c) +4
• d) +2

Answer: +3

Question: Which of the following ions having following electronic structure would have maximum magnetic moment?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: If n is the number of unpaired electrons, the magnetic moment (in BM) of transition metal/ion is given by

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which one of the following ions has the maximum magnetic moment?

• a) Fe³⁺
• b) Ti³⁺
• c) Sc³⁺
• d) Cr³⁺

Answer: Fe³⁺

Question: The magnetic nature of elements depend on the presence of unpaired electrons. Identify the configuration of transition element, which shows highest magnetic moment

• a) 3d ⁵
• b) 3d ²
• c) 3d⁷
• d) None of these

Answer: 3d ⁵