d and f-Block Elements Quiz

1

A transition element is defined as an element whose atom or ion has:

Complete d-subshell Incomplete d-subshell (1-9 electrons) Only s-electrons p-block configuration

2

The general electronic configuration of d-block elements is:

ns² np⁶ (n-1)d¹⁻¹⁰ ns¹⁻² (n-2)f¹⁻¹⁴ ns² ns¹

3

Zn, Cd, Hg are excluded from transition elements because they have:

Incomplete d-subshell Complete d¹⁰ configuration Variable oxidation states High melting points

4

The anomalous configuration of Cr (24) is:

[Ar] 3d⁴ 4s² [Ar] 3d⁵ 4s¹ [Ar] 3d³ 4s² [Ar] 3d⁶ 4s⁰

5

Atomic radii of d-block elements across a series:

Increase regularly Decrease regularly to minimum in middle, then slight increase Remain constant Increase to maximum at end

6

Nearly equal atomic radii in 4d and 5d series is due to:

Poor shielding by f-electrons (Lanthanide contraction) High nuclear charge Addition of new shell d-electron pairing

7

Ionization energies of transition elements are:

Lower than s-block Higher than s-block, between s and p-block Same as p-block Very low

8

Melting points of transition elements are high due to:

Weak metallic bonds Strong metallic bonds with covalent character Ionic bonding No unpaired electrons

9

Maximum melting point in 3d series is at:

Sc Cr (5 unpaired electrons) Zn Cu

10

Variable oxidation states in transition elements are due to:

Only ns electrons Participation of ns and (n-1)d electrons f-electrons p-electrons

11

Most common oxidation state for first transition series (except Sc) is:

+1 +2 +3 +4

12

Highest oxidation state shown by any transition metal is:

+6 (Cr) +7 (Mn) +8 (Ru, Os) +4 (Ti)

13

Standard electrode potential for Cu²⁺/Cu is:

-0.76 V +0.34 V -1.18 V -0.44 V

14

Transition metal compounds are colored due to:

d-d transition of electrons Charge transfer f-f transition s-p transition

15

The color of Cu²⁺ ion is:

Green Blue Yellow Violet

16

Transition elements show paramagnetism due to:

Paired electrons Unpaired d-electrons Complete d-orbitals s-electrons

17

Maximum paramagnetism in 3d series is shown by ions with:

1 unpaired electron 5 unpaired electrons (e.g., Mn²⁺, Fe³⁺) 0 unpaired electrons 3 unpaired electrons

18

High enthalpies of atomization in transition metals are due to:

Weak bonds Strong metallic bonds from valence electrons Ionic character No d-electrons

19

All transition elements are:

Non-metals Metals with high conductivity and malleability Gases Poor conductors

20

Non-typical transition elements include:

Only group 3 Group 3 (Sc, Y, La, Ac) and group 12 (Zn, Cd, Hg) Only group 12 s-block elements