MHS Chemistry
Light and Energy Worksheet

For ease of typing, I will write numbers in scientific notation using "n" for "x10-" and "p" for "x10+"
Planck's constant is therefore 6.63n34 and the speed of light is 3.0p8             Got it?

Table 1
Constants & Relations
Table 2
Colors, & Information
E = hn
c = ln
h = 6.63n34 J/Hz
c = 3.00p8 m/s
1 m = 102 cm = 109 nm
1 nm = 10-9 m
1 Hz = 1 wave/sec
 DE = hn = -2.18n18 J é1 __ 1ù ënf2 ni2û
 color wavelength (l) frequency (n) [nm] [p14 Hz] UV <400 >7.5 violet 400 to 420 7.5 to 7.1 blue 420 to 490 7.1 to 6.1 green 490 to 580 6.1 to 5.2 yellow 580 to 590 5.2 to 5.1 orange 590 to 650 5.1 to 4.6 red 650 to 700 4.6 to 4.3 IR >700 <4.3

1. Fill in the blanks in the following table:

 element symbol atomic # p+ n0 e- mass # atomic weight charge C 8 6 Yttrium 36 86 Iron 31 23 35 45 1- 11 20.1797 0 H 2 1 Potassium 19 18 92 235 6+ 9 19 1-

2. Fill in the blanks in the following table:

 particle symbol mass (amu) charge location proton p+ neutron electron

3. An electron [gains, loses] energy when it emits a photon of light.
4. [Infrared, Visible, Ultraviolet] light has the highest frequency.
5. [Infrared, Visible, Ultraviolet] light has the most energy.
6. [Infrared, Visible, Ultraviolet] light has the highest wavelength.
7. [Red, Violet] light has the higher frequency.
8. [Red, Violet] light has the higher wavelength.
9. [l, n] is the symbol for frequency, and [l, n] is the symbol for wavelength.

10. Fill in the blanks in the following table:

 "floating point" scientific notation "silly" 4.21n3 -- 12,900 -- 451n9 0.0000834 -- 659,000,000,000,000 -- 3.0p8 -- 0.006p5

11. Convert 522 nm to m.

12. Convert 4.44n7 m to nm.

13. What is the wavelength of a photon with frequency 5.7p14 Hz?  What color is it?

14. What is the frequency of a photon with wavelength 6.2n7 m?  What color is it?

15. What is the energy of a photon with frequency 7.3p14 Hz?  What color is it?

16. What is the energy of a photon with wavelength 600 nm?  What color is it?

17. What is the speed of a water wave with frequency 5 waves/min and wavelength 13 m?

18. What is the frequency of a photon with wavelength 565 nm?  What color is it?

19. What is the frequency of a photon with energy of 6.22n19 J?  What color is it?

20. What is the wavelength of a photon with energy 5.5n19 J?  What color is it?

21. How does the line emission spectrum of a pure sample of an element compare with
its line absorption spectrum?

22. What is the energy of a photon produced by an electron moving from n=5 to n=2?