Intro chem help! Visible light spectrum? and energy of photon? help!

  • Thread starter nchin
  • Start date
  • #1
172
0
on a visible spectrum scale what are the numbers for the colors of ROYGBIV? for example is violet 400-500nm and red is 700-800nm? how about the other colors?

If the energy of a photon is 2.63 x 10^-19 J, how can we tell what color this is? i was looking at this electromagnetic spectrum and it doesnt help me much.
http://www.lbl.gov/MicroWorlds/ALSTool/EMSpec/EMSpec2.html

help!
 

Answers and Replies

  • #3
172
0
I don't know where you got your wavelength ranges for the different colors. Here are a couple of different references:

http://en.wikipedia.org/wiki/Visible_spectrum#Spectral_colors
http://www.giangrandi.ch/optics/spectrum/spectrum.shtml

As far as the energy of a photon is concerned, look up Planck's constant.

One of my hw ques ask what is the wave length of 755nm and the answer is red.
how is 755nm wavelength = red? the charts shows that red is only up to 700.
 
  • #4
Ygggdrasil
Science Advisor
Insights Author
Gold Member
3,427
3,910
How people refer to color is somewhat subjective. However, I would probably call 755 nm light infrared rather than red.
 

Related Threads on Intro chem help! Visible light spectrum? and energy of photon? help!

Replies
3
Views
4K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
1
Views
7K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
3
Views
1K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
1
Views
3K
Top