State PCS PYQPrelims 2023

UPPCS · प्रश्न 79

Which of the following elements is NOT a noble gas?

  1. Radon
  2. Krypton
  3. Argon
  4. Actinium
उत्तर देखें और व्याख्या

उत्तर: (D) Actinium

व्याख्या

Actinium is an actinide metal; radon, krypton and argon are Group 18 noble gases.