Packets of light emitted from a hydrogen atom have the following wavelengths:

Wavelength (nm) / 94 / 95 / 97 / 103 / 122 / 410 / 434 / 486 / 656 / 1094 / 1282 / 1875

1) Draw the wavelengths as lines on the axis below. The first two have been done for you.

2) Identify the regions of the electromagnetic spectrum as IR, Visible and UV.

3) How many wavelengths appear in the visible region? What colors are these lines?

4) Label wavelengths (94-122 the Lyman series; 410 – 665 the Balmer series; 1094 – 1875 the Paschen series)

Select 2 lines in the visible section and solve for the frequency and energy of these lines, using the relationships between wavelength and frequency and between frequency and energy.

c = 3.0 x 108 m/s, h = 6.63 x 10-34 J

Convert nm to m

Wavelength (nm) / Color / Frequency (Hz) / Energy (J)
410
4.10 x 10-7m / violet / c = fλ=
7.3 x 1014 / E = hf =
4.85 x 10-19

Questions to answer

Why do hot object glow and why does the color of the glow change predictably?

Why do solar panels create electricity?

Why do gases glow when an electric current is run through them?

What gives fireworks their color?

What gives fire its color?

Atomic Emission Spectrum

1.Look at the spectrum at the top of this page and determine the colors of the following four spectral lines? These are the four emission lines in the visible part of the spectrum for hydrogen.

410 nm ______/ 432 nm ______/ 486 nm ______/ 656 nm ______

Keep in mind that c =and E = h c = 3.0 x 108 m/s, h = 6.63 x 10-34 J

Radio / Gamma Rays / X-rays / Visible Light / Microwaves / Infrared / Ultraviolet

2.Arrange the bands of light above in order from longest wavelength on the left to shortest wavelength on the right.

3.Arrange the same bands of light above in order from lowest frequency on the left to highest frequency on the right.

4.Arrange the same bands of light above in order from highest energy on the left to lowest energy on the right.

5.Which color of visible light has…

a) the shortest wavelength? ______c) the least amount of energy? ______

b) the longest wavelength? ______d) the greatest amount of energy? ______

6.The drawing on the right depicts only four of the many possible energy levels around the nucleus of an atom. Answer the following questions:
a) Draw arrows between energy levels for all possible energy transitions for this atom.
b) How many spectral lines will this atom produce from these energy levels? /
c) Which transition (from n = ___ to n = ___ ) will give you the highest frequency (shortest wavelength) of light?
d) Which transition (from n = ___ to n = ___ ) will give you the lowest frequency (longest wavelength) of light?

7.How does a hydrogen atom, which has only one electron, have so many spectral lines?