Chemistry
Answered
Aufbau principle, electronic configuration
Why does the 4s orbital fill before 3d?
Isn’t 3d supposed to come first?
Curious Corner
Sep 01, 2025
1
Answers
190
Views
Answers 1
Curious Corner
Answered Recently
It’s because the energy of 4s is slightly lower than 3d due to shielding and penetration effects. Hence, electrons prefer 4s before 3d when filling.
Login to Answer
Join the community to provide answers and help other students. Your expertise can make a difference!
It only takes a minute to get started.
Related Questions
Percentage Composition
Chemistry
391
1
Bragg’s Law
Chemistry
386
1
Why does milk turn sour in summer?
Chemistry
385
1
Quick Actions
Community Stats
542
Questions
547
Answers
12
Students
6
Subjects