PYQSide ExamsMy practice

d- and f-Block Elements · Question 10

JEE Main 2026 (Online) 4th April Evening ShiftMCQMedium📈 Topic in 3% papers+4−1
1

Pairs of elements with the same number of electrons in their respective 4f orbital are [Atomic number. Eu-63, Gd-64, Dy-66, Ho-67, Tm-69, Yb-70, Lu-71, Hf-72] Choose the correct answer from the options given below :

  1. B and C Only
  2. A and B Only
  3. A and D Only
  4. A and C Only

Answer

(4) A and C Only

Solution

Electronic configurations ([Xe] core):

Eu (63): 4f7 6s2 → 7; Gd (64): 4f7 5d1 6s2 → 7 ⇒ A ✓ (stable half-filled 4f)

Dy (66): 4f10 6s2 → 10; Ho (67): 4f11 6s2 → 11 ⇒ B ✗

Yb (70): 4f14 6s2 → 14; Hf (72): 4f14 5d2 6s2 → 14 ⇒ C ✓

Lu (71): 4f14 5d1 6s2 → 14; Tm (69): 4f13 6s2 → 13 ⇒ D ✗

∴ A and C

Answer: (4)

JEE Main 2026 (Online) 4th April Evening Shift

Keep practising — d- and f-Block Elements

2

Consider |x| is the difference in oxidation states of Mn in highest manganese fluoride and highest manganese oxide. The ions with |x| number of unpaired electrons from the following are : Choose the correct answer from the options given below :

  1. A and B Only
  2. C, D and E Only
  3. C and E Only
  4. B and E Only
JEE Main 2026 (Online) 4th April Evening Shift
3

Which of the following sets includes all the species that will change the orange colour of K2Cr2O7 in acidic medium ?

  1. Fe2+, Sn2+, I-, S2-
  2. S2-, Fe3+, I-, C2O42-
  3. Fe2+, NO2-, SO2, Sn4+
  4. Fe3+, SO42-, S2-, Sn4+
JEE Main 2026 (Online) 2nd April Morning Shift
4

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

  1. Both Statement I and Statement II are true
  2. Both Statement I and Statement II are false
  3. Statement I is true but Statement II is false
  4. Statement I is false but Statement II is true
JEE Main 2026 (Online) 2nd April Evening Shift
5

Among Fe2+, Fe3+, Cr2+ and Zn2+, the ion that shows positive borax bead test and with highest ionisation enthalpy is :

  1. Fe2+
  2. Zn2+
  3. Cr2+
  4. Fe3+
JEE Main 2026 (Online) 2nd April Evening Shift
6

Number of paramagnetic ions among the following d- and f-block metal ions is . Mn2+, Cu2+, Zn2+, Yb2+, Sc3+, La3+, Gd3+, Lu3+, Ti4+, Ce4+ (Atomic number of Mn = 25, Cu = 29, Zn = 30, Yb = 70, Sc = 21, La = 57, Gd = 64, Lu = 71, Ti = 22, Ce = 58)

JEE Main 2026 (Online) 2nd April Evening Shift
7

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below

  1. Statement I is false but Statement II is true
  2. Both Statement I and Statement II are false
  3. Both Statement I and Statement II are true
  4. Statement I is true but Statement II is false
JEE Main 2026 (Online) 28th January Morning Shift
8

Consider the following statements about manganate and permanganate ions. Identify the correct statements. Choose the correct answer from the options given below :

  1. A and D Only
  2. A, B and C Only
  3. A, C and D Only
  4. A, D and E Only
JEE Main 2026 (Online) 28th January Evening Shift
9

"X" is an oxoanion of the lightest element of group 7 (in the periodic table). The metal is in +6 oxidation state in "X". The color of the potassium salt of X is

  1. purple
  2. orange
  3. yellow
  4. green
JEE Main 2026 (Online) 24th January Evening Shift
10

The oxidation state of chromium in the final product formed in the reaction between KI and acidified K2Cr2O7 solution is :

  1. +2
  2. +3
  3. +4
  4. +6
JEE Main 2026 (Online) 23rd January Evening Shift
11

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

  1. Statement I is true but Statement II is false
  2. Both Statement I and Statement II are true
  3. Both Statement I and Statement II are false
  4. Statement I is false but Statement II is true
JEE Main 2026 (Online) 22nd January Evening Shift

All d- and f-Block Elements PYQs →

PDFDownload d- and f-Block Elements PYQs as PDF Free, with answer key and a QR code to every solution — print it or study offline⬇
All JEE Main Chemistry chapters