Question

The wavelength of the first line of the Lyman series of a ten times ionised sodium atom (Z = 11) is nearly-

• A. 1216 Å
• B. (\frac{1216}{11})Å
• C. (\frac{1216}{(11)^{2}})Å
• D. (\frac{1216}{(11)^{3}})Å

Answer 1

Answer: (C)

$\frac{1216}{(11)^{2}}$Å

Answer 2

$\frac{1}{\lambda} = RZ^{2}\left\lbrack \frac{1}{1^{2}} - \frac{1}{2^{2}} \right\rbrack$

\ $\frac{1}{\lambda}$ = (11)² (1.097 ×10⁷) $\left( \frac{3}{4} \right)$

\ l = $\frac{1216}{(11)^{2}}$Å