En=−2.18×10−18×n2Z2J For He+⇒E1=−2.18×10−18×1222 J=−8.72×10−18 J For Li2+⇒E1=−2.18×10−18×1232 J=−19.62×10−18 Jrn=52.9×Zn2pm For He+⇒r1=52.9×212pm=26.4pm For Li2+⇒r1=52.9×312pm=17.6pm
NEET UG 2025 — Chemistry Physical Chemistry
Energy and radius of first Bohr orbit of He+and Li2+ are [Given RH=2.18×10−18 J,a0=52.9pm ]
Held on 30 Apr 2025 · Verified 9 Jul 2026.
En(Li2+)=−19.62×10−18 J;rn(Li2+)=17.6pmEn(He+)=−8.72×10−18 J;rn(He+)=26.4pm
En(Li2+)=−8.72×10−18 Jrn(Li2+)=26.4pmEn(He+)=−19.62×10−18 J;rn(He+)=17.6pm
En(Li2+)=−19.62×10−16 Jrn(Li2+)=17.6pmEn(He+)=−8.72×10−16 Jrn(He+)=26.4pm
En(Li2+)=−8.72×10−16 Jrn(Li2+)=17.6pmEn(He+)=−19.62×10−16 J;rn(He+)=17.6pm
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