Question
Two elements X and Y in the same Mendeleev group both form RH_4 and RO_2 ; if the atomic mass of X is lower than Y, how would they be placed?
Asked in MP Police Constable · 2025
Genesis of Periodic Classification · Chemistry
Exam PYQ4 Options
Quick Revision
Elements in the same group often have similar valence-electron configurations.
Correct AnswerCorrect option for this question
Learn Genesis of Periodic Classification in 60 Seconds
Watch Mendeleev Periodic Table for a focused recap of the concept before moving to similar practice questions.
Everything you need to learn, practice & excel — in one place.
3,000+ Video-Based Study Material
PYQ-Based Quizzes
4,000+ Informative Audiobooks
6,300+ Full-Length Mock Tests
Daily Current Affairs
40,000+ PYQs
Questions Asked from Mendeleev Periodic Table in Previous Exams
See how often Mendeleev Periodic Table has appeared in previous-year questions across major government exams.
7UPSC Questions Asked in These Years:2010, 2011, 2012, 2013, 2019, 2020, 2024
8SSC Questions Asked in These Years:2017, 2019, 2020, 2021, 2022, 2023, 2024, 2025
7Railways Questions Asked in These Years:2016, 2018, 2021, 2022, 2024, 2025, 2026
13State PSC Questions Asked in These Years:2002, 2004, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025
Mendeleev Periodic Table has appeared in 35 previous-year exam questions, most frequently in State PSC, SSC and UPSC.
2-Minute Revision Notes
Revise Genesis of Periodic Classification and Its Related Concepts
Strengthen key concepts with exam-focused visual notes for faster revision.
Explore More Questions
Continue practising by chapter, topic and related subjects.
One question solved. Keep going.
Continue with the next Classification of Elements and Periodicity in Properties question and build your accuracy one question at a time.