Question

The wave number of the first line on the Balmer series of hydrogen is 15200$c{m}^{-1}$. What would be the wave number of the first line in the Lyman series of the $B{e}^{3+}$ ion?

• A. 2.4 ×10⁵ cm^-1
• B. 24.3 ×10⁵ cm^-1
• C. 6.08 ×10⁵ cm^-1
• D. 1.313×10⁶ cm^-1

Answer 1

The correct option is C.

1.313×10⁶ cm^-1

Given:

The wave number of the first line on the Balmer series of hydrogen= 15200 ${cm}^{-1}$

15200 = R($1^2$)($\frac{1}{2^2}$-$\frac{1}{3^2}$)......(i)

$\overline{\upsilon }$ = $R$($4^2$)($\frac{1}{1^2}$-$\frac{1}{2^2}$).........(ii)

From (i) and (ii) equation:

$\overline{\upsilon }$=$1.313\times {10}^{6}c{m}^{-1}$