MCQ practice · SSC Chemistry Board questions · Chapter 4: Periodic Table
Which element is an exception when the group is found by the configuration rules?
Think it through first, then pick an option.
- a He
- b Al
- c K
- d Cu
Answer and explanation
Correct answer: a He
He (1s²) gets group 2 by rule 1 but sits in group 18.
Why the other options are wrong
- b Al: Al's group fits rule 2: 13. The answer is He.
- c K: K's group fits rule 1: 1. The answer is He.
- d Cu: Cu's group fits rule 3: 11. The answer is He.
Your account is open, so all 30,000+ MCQs from every chapter are yours. Start practising SSC Chemistry →
Want to keep going?
A free account carries you on to the next questions and opens 30,000+ MCQs from every chapter. Join before launch and Chirkut bundles are 60% off.
The ones you missed, worth one more look