What is the experimental evidence in support of the idea that electronic energies in an atom are quantized ?

What is the experimental evidence in support of the idea that electron

1.	What is the experimental evidence in support of the idea that electronic energies in an atom are quantized ?
Answer» Solution :The line spectrum of any element has lines corresponding to definite wavelengths. Lines are obtained as a result of electronic transitions The w avelength is DISTANCE betw een TWO SUCCESSIVE peaks or two successive troughs of a wave. So, X = 4 x 2.16 pm = 8.64 pm 37 between the ENERGY levels. So, the electrons in these levels have fixed energy, i.e., quantized values.