Chemistry · PYQ NEET UG 2025

हाइड्रोजन सदृश प्रजातियों \( \text{He}^+ \) तथा \( \text{Li}^{2+} \) की प्रथम बोर कक्षा की ऊर्जा और त्रिज्या हैं [दिया गया है \( R_H = 2.18 \times 10^{-18} \text{ J}, a_0 = 52.9 \text{ pm} \)]

1. A
   \( E_n(\text{Li}^{2+}) = -19.62 \times 10^{-18} \text{ J}; r(\text{Li}^{2+}) = 17.6 \text{ pm}; E_n(\text{He}^+) = -8.72 \times 10^{-18} \text{ J}; r_n(\text{He}^+) = 26.4 \text{ pm} \)
2. B
   \( E_n(\text{Li}^{2+}) = -8.72 \times 10^{-18} \text{ J}; r(\text{Li}^{2+}) = 26.4 \text{ pm}; E_n(\text{He}^+) = -19.62 \times 10^{-18} \text{ J}; r_n(\text{He}^+) = 17.6 \text{ pm} \)
3. C
   \( E_n(\text{Li}^{2+}) = -19.62 \times 10^{-16} \text{ J}; r(\text{Li}^{2+}) = 17.6 \text{ pm}; E_n(\text{He}^+) = -8.72 \times 10^{-16} \text{ J}; r_n(\text{He}^+) = 26.4 \text{ pm} \)
4. D
   \( E_n(\text{Li}^{2+}) = -8.72 \times 10^{-16} \text{ J}; r_n(\text{Li}^{2+}) = 17.6 \text{ pm}; E_n(\text{He}^+) = -19.62 \times 10^{-16} \text{ J}; r_n(\text{He}^+) = 17.6 \text{ pm} \)