Practice portal › Atoms › Hydrogen Spectrum and Transitions

The number of spectral lines in the hydrogen atom is

Asked in GUJCET 2015 · Number of spectral lines

Answer: (4) Infinite

Step-by-step solution

Idea: every spectral line comes from a jump between two energy levels.

If atoms are excited as far as level n, the number of different lines possible is (n(n-1))/2.

Hydrogen has infinitely many levels, n=1,2,3,…, crowding together just below the ionisation limit.

With no upper limit on n, the count (n(n-1))/2 grows without bound.

So hydrogen has an infinite number of spectral lines; each series has infinitely many lines converging on its series limit.

Why the other options are wrong

More Hydrogen Spectrum and Transitions questionsAll Hydrogen Spectrum and Transitions questions →

Reading this solution needs no sign-in. You only sign in to practise against the clock and keep your progress.

Practise this with a timer