Which energy state of the triply ionized beryllium (Be+++) has the same electrons orbital radius as that of the ground state of hydrogen? Given Zfor beryllium = 4.
n = 2
for an atom of atomic number Z, the radius of the nth orbit is given by
Where is a constant. For the ground state of hydrogen (Z = 1),n = 1 so that
r1 = K
let n be the energy state of Be+++ for which the orbital is r1. Putting Z = 4 and rn = r1 = K is eq. (i) we get
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