Question

Maximum emitted wavelength by photon during a transition in $H-$atom that produce a visible light $\left(\frac{1}{R}\right)=912\mathring{A},R\Rightarrow$ Rydberg constant ) is(approx):

• A. $1213\mathring{A}$
• B. $3536\mathring{A}$
• C. $6566.4\mathring{A}$
• D. $7172.3\mathring{A}$

Answer 1

The correct option is A $1213\mathring{A}$

Maximum wavelength of an photon is emitted during transition from

$n=2\to n=1$ I.e. for lyman series

$\frac{1}{{\lambda }_{max}}=R(\frac{1}{n_1^2}-\frac{1}{n_2^2})$

$R=\frac{1}{912\stackrel{o}{A}}$ is Rydberg's constant

$\frac{1}{{\lambda }_{max}}=\frac{1}{912\stackrel{o}{A}}(\frac{1}{1}-\frac{1}{4})$

${\lambda }_{max}=1213\stackrel{o}{A}$