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Question
The Li2+ ion is a hydrogen like ion that can be described by the Bohr model. Calculate the Bohr radius of the third orbit and calculate the energy of an electron in 4th orbit.
Solution
rn = `((0.529)"n"^2)/("z")` Å
En = `(-13.6 ("z"^2))/("n"^2)` ev atom−1
for Li2+ z = 3
Bohr raduis for the third orbit (r3)
= `((0.529)(3)^2)/3`
= 0.529 × 3
= 1.587 Å
Energy of an electron in the fourth orbit (E4) = `(-13.6(3)^2)/(4)^2`
= –7.65 eV atom–1
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