If a neon atom has an transition that emits light with a wavelength of #7.33xx10^7# m, what color of light is given off? How much energy is given off?

1 Answer
Mar 9, 2017

The energy of the wavelength #7.33xx10^7#m is #2.71xx10^(-33)color(white)(.)"J"#.

Explanation:

#7.33xx10^7"m"# is not a wavelength in the visible light electromagnetic spectrum. It would be a radio wave because they have the longest wavelengths.

Calculate energy.

We can still calculate energy using the equation:

#E=(hc)/lambda#

where #E# is energy in Joules (J), #c# is the speed of light, and

#lambda# (pronounced "lambda") is the wavelength.

#h= 6.62606896xx10^(−34) "J·s"#, and is known as Planck's constant.

#c="299792458 m/s"#, and is the speed of light in a vacuum.

Substitute the known values into the equation.

#E=(6.62606896xx10^(−34) "J"·cancel"s"xx299792458 cancel("m")/cancel"s")/(7.33xx10^7cancel"m")=2.71xx10^(-33) "J"# (rounded to three significant figures)

Many people use #3.00xx10^8# m/s for the speed of light rounded to three significant figures, and #6.626xx10^(-34)# #"J"*"s"# for Planck's constant rounded to four significant figures.

The wavelength #7.33xx10^7# m is in the Extremely Low Frequency (ELF) end of the electromagnetic spectrum, which are radio waves Megameters (Mm) in length.

#"1 Mm"=1xx10^6" m"#

#(7.33xx10^7cancel"m")xx(1"Mm")/(1xx10^6cancel"m")="73.3 Mm"#

https://en.wikipedia.org/wiki/Electromagnetic_spectrum