UPSC CAPF AC 2024 Paper 1 · Question 20

Question 20 of the UPSC CAPF (AC) 2024 Paper I (4 August 2024). Try it first, then open the answer and explanation.

1. CAPF 2024 · P-I · Q20 · General Science · Chemistry

   Match List I with List II and select the correct answer using the code given below the Lists: List I (Element) List II (Unpaired electron) A. Boron 1. Zero B. Nitrogen 2. Two C. Oxygen 3. One D. Neon 4. Three

   1. A-1, B-4, C-2, D-3
   2. A-1, B-2, C-4, D-3
   3. A-3, B-2, C-4, D-1
   4. A-3, B-4, C-2, D-1

   सूची I को सूची II से सुमेलित कीजिए और सूचियों के नीचे दिए गए कूट का प्रयोग कर सही उत्तर चुनिए : सूची I (तत्त्व) सूची II (अयुग्मित इलेक्ट्रॉन) A. बोरॉन 1. शून्य B. नाइट्रोजन 2. दो C. ऑक्सीजन 3. एक D. निऑन 4. तीन

   1. A-1, B-4, C-2, D-3
   2. A-1, B-2, C-4, D-3
   3. A-3, B-2, C-4, D-1
   4. A-3, B-4, C-2, D-1
   Show answer

   Answer: (4) A-3, B-4, C-2, D-1

   उत्तर: (4) A-3, B-4, C-2, D-1

   Boron (2s^2 2p^1) has one unpaired electron; nitrogen (2p^3) puts its three 2p electrons in separate orbitals by Hund's rule, so three; oxygen (2p^4) has two; and neon (2p^6) has a filled shell with none. Hence A-3, B-4, C-2, D-1.

Answer it in the practice appMake a topic-wise quiz