4d Series Elements: The Complete List

The 4d series elements are the second row of transition metals in the periodic table, comprising elements from Yttrium (Y) to Cadmium (Cd). These elements fill their 4d orbitals progressively across the series.

Yttrium (Y)

Atomic Number: 39

Electronic Configuration: [Kr] 4d1 5s2

Discovered in 1794 by Johan Gadolin

Zirconium (Zr)

Atomic Number: 40

Electronic Configuration: [Kr] 4d2 5s2

Used in nuclear reactors

Niobium (Nb)

Atomic Number: 41

Electronic Configuration: [Kr] 4d4 5s1

Formerly known as Columbium

Molybdenum (Mo)

Atomic Number: 42

Electronic Configuration: [Kr] 4d5 5s1

Essential trace element in biology

Technetium (Tc)

Atomic Number: 43

Electronic Configuration: [Kr] 4d5 5s2

The first artificially produced element

Ruthenium (Ru)

Atomic Number: 44

Electronic Configuration: [Kr] 4d7 5s1

Used in electrical contacts

Rhodium (Rh)

Atomic Number: 45

Electronic Configuration: [Kr] 4d8 5s1

One of the rarest elements

Palladium (Pd)

Atomic Number: 46

Electronic Configuration: [Kr] 4d10

Used in catalytic converters

Silver (Ag)

Atomic Number: 47

Electronic Configuration: [Kr] 4d10 5s1

Best electrical conductor

Cadmium (Cd)

Atomic Number: 48

Electronic Configuration: [Kr] 4d10 5s2

Used in rechargeable batteries

Advertisement

Electronic Configuration of 4d Series Elements

The 4d series elements electronic configuration follows the general pattern of transition metals, but with some exceptions due to the stability of half-filled and completely filled d orbitals.

4d series elements electronic configuration diagram

The general electronic configuration of 4d series is [Kr] 4d1-10 5s0-2, where Kr represents the electron configuration of Krypton (the preceding noble gas).

Special Cases in 4d Series Configuration

Some elements deviate from the expected configuration due to increased stability:

Element Expected Configuration Actual Configuration Reason
Niobium (Nb) [Kr] 4d3 5s2 [Kr] 4d4 5s1 Half-filled d subshell stability
Molybdenum (Mo) [Kr] 4d4 5s2 [Kr] 4d5 5s1 Half-filled d subshell stability
Ruthenium (Ru) [Kr] 4d6 5s2 [Kr] 4d7 5s1 Higher stability
Rhodium (Rh) [Kr] 4d7 5s2 [Kr] 4d8 5s1 Higher stability
Palladium (Pd) [Kr] 4d8 5s2 [Kr] 4d10 Completely filled d subshell

4d Series Configuration Generator

Select an element to see its electronic configuration:

Advertisement

Memory Tricks for 4d Series Elements

Learning all the 4d series elements names and their electronic configuration of 4d series can be challenging. Here are some helpful mnemonics:

English Mnemonic for 4d Series

Sentence: “Yes, Zebras Need More Technical Running Rhythms Particularly Since Cadillacs”

Elements: Y (Yttrium), Zr (Zirconium), Nb (Niobium), Mo (Molybdenum), Tc (Technetium), Ru (Ruthenium), Rh (Rhodium), Pd (Palladium), Ag (Silver), Cd (Cadmium)

Hindi Mnemonic (4d Series Elements Trick in Hindi)

Sentence: “यशवंत ज़रा नमक मिला तक रुका रहा पद्मा सोना चढ़ा”

Elements: Y (Yttrium), Zr (Zirconium), Nb (Niobium), Mo (Molybdenum), Tc (Technetium), Ru (Ruthenium), Rh (Rhodium), Pd (Palladium), Ag (Silver), Cd (Cadmium)

Configuration Pattern Trick

Remember these key points about d block elements electronic configuration of 4d series:

  • All start with [Kr] core
  • First three (Y, Zr, Nb) follow normal pattern
  • Mo and Tc show half-filled stability
  • Ru and Rh show unexpected 5s1 configuration
  • Pd is unique with completely filled 4d and empty 5s
  • Ag and Cd return to normal pattern

4d Series in the Periodic Table

The 4d series in periodic table occupies period 5, groups 3 through 12. These elements bridge the gap between the lighter 3d series and heavier 5d series transition metals.

Key characteristics of periodic table 4d series elements:

  • All are metals with high melting and boiling points
  • Show variable oxidation states
  • Form colored compounds
  • Many act as catalysts
  • Generally less reactive than 3d series
  • More dense than 3d series elements

4d Series Properties Comparison

Select two elements to compare their properties:

Test Your Knowledge: 4d Series Quiz

Challenge yourself with these questions about 4d series configuration and properties!

Question 1:

Which element in the 4d series has the electronic configuration [Kr] 4d5 5s1?

Further Learning Resources

Expand your chemistry knowledge with these related topics:

Frequently Asked Questions

What is the electronic configuration of 4d series elements?
The general electronic configuration of 4d series elements is [Kr] 4d1-10 5s0-2, where Kr represents the electron configuration of Krypton. However, some elements like Niobium, Molybdenum, Ruthenium, Rhodium, and Palladium show exceptions to this pattern due to the stability of half-filled or completely filled d orbitals.
Why do some 4d series elements have unusual electronic configurations?
Some 4d series elements have unusual electronic configurations because half-filled and completely filled d subshells are more stable than partially filled ones. This stability causes electrons to move from the 5s to the 4d orbital in elements like Niobium, Molybdenum, Ruthenium, and Rhodium. Palladium is unique with a completely filled 4d subshell and no 5s electrons.
How many elements are in the 4d series?
There are 10 elements in the 4d series, ranging from Yttrium (Y) with atomic number 39 to Cadmium (Cd) with atomic number 48. These elements occupy period 5, groups 3 through 12 of the periodic table.
What are the common properties of 4d series elements?
4d series elements share several common properties: they are all metals with high melting and boiling points, show variable oxidation states, form colored compounds, many act as catalysts, are generally less reactive than 3d series elements, and are more dense than 3d series elements.
What is the easiest way to remember the 4d series elements?
A popular mnemonic for remembering the 4d series elements is “Yes, Zebras Need More Technical Running Rhythms Particularly Since Cadillacs,” which stands for Yttrium, Zirconium, Niobium, Molybdenum, Technetium, Ruthenium, Rhodium, Palladium, Silver, and Cadmium.

Student Testimonials

This guide on 4d series elements electronic configuration helped me understand the exceptions in electron configurations that I was struggling with in my chemistry class. The memory tricks were especially useful!

– Sarah K., Chemistry Student

As a chemistry tutor, I recommend this resource to all my students. The interactive tools and clear explanations make complex concepts accessible.

– Michael R., Chemistry Tutor

I was preparing for my competitive exams and found this guide incredibly helpful. The quiz section tested my knowledge effectively.

– Priya S., Exam Candidate

References and Further Reading

  1. Housecroft, C. E., & Sharpe, A. G. (2012). Inorganic Chemistry (4th ed.). Pearson Education.
  2. Cotton, F. A., Wilkinson, G., Murillo, C. A., & Bochmann, M. (1999). Advanced Inorganic Chemistry (6th ed.). John Wiley & Sons.
  3. Miessler, G. L., Fischer, P. J., & Tarr, D. A. (2014). Inorganic Chemistry (5th ed.). Pearson Education.
  4. IUPAC. (2019). Periodic Table of the Elements. International Union of Pure and Applied Chemistry.
  5. Greenwood, N. N., & Earnshaw, A. (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann.
Dr. Rebecca Thompson

About the Author

Dr. Rebecca Thompson, PhD

Dr. Rebecca Thompson is a renowned chemist with over 15 years of experience in inorganic chemistry and education. She holds a PhD in Inorganic Chemistry from the Massachusetts Institute of Technology and has conducted extensive research on transition metal complexes.

Dr. Thompson has published numerous research papers in prestigious journals including the Journal of the American Chemical Society and Inorganic Chemistry. She has also authored several textbooks on inorganic chemistry that are used in universities worldwide.

With a passion for making complex chemistry concepts accessible to students, Dr. Thompson has developed innovative teaching methods and has received multiple awards for excellence in education, including the National Science Foundation’s CAREER Award.

When not researching or teaching, Dr. Thompson enjoys developing educational resources like this guide to help students master challenging topics in chemistry.