The difference between the radii of 3rd and 4th
orbits of Li2+ is R1
. The difference between the
radii of 3rd and 4th orbits of He+ is
$\Delta$R2
.
Ratio $\Delta$R1 : $\Delta$R2 is :
Solution
R<sub>n</sub> = a<sub>0</sub>${{{n^2}} \over Z}$
<br><br>$${{\Delta {R_1}} \over {\Delta {R_2}}} = {{{{\left( {{r_4} - {r_3}} \right)}_{L{i^{2 + }}}}} \over {{{\left( {{r_4} - {r_3}} \right)}_{H{e^ + }}}}}$$
<br><br>= $${{{{{4^2}} \over 3} - {{{3^2}} \over 3}} \over {{{{4^2}} \over 2} - {{{4^2}} \over 2}}}$$ = ${{7/3} \over {7/2}} = {2 \over 3}$
About this question
Subject: Chemistry · Chapter: Atomic Structure · Topic: Bohr's Model
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