The wave number of the last line of the Balmer series in hydrogen spectrum will be (Rydberg's constant =10^7 ~m ⁻¹ )

Step-by-step solution

We know that: 1 =R ( 1 n₁^2 - 1 n₂^2 ) For last line Balmer's series, n₁=2, n₂= So, 1 =10^7 ( 1 2^2 - 1 ^2 )=0.25 10^7 ~m ⁻¹