Why each element gives off its own colors

Answer Key - Grade 10 Science Worksheet

Circle the best answer, or write your answer on the line.

1. 1.

   A hydrogen photon carries 2.55 eV. With hc = 1239.84 eV·nm, what is its wavelength, to 0.01 nm, Bo?

   486.21 nm
2. 2.

   A hydrogen photon carries 2.86 eV. With hc = 1239.84 eV·nm, what is its wavelength, to 0.01 nm, Esme?

   433.51 nm
4. 3.

   Using the table, which element is the unknown gas, Jun?

   • Hydrogen
   • Sodium vapor
   • Helium
5. 4.

   Using the table, which hydrogen line is reddest, Luz?

   Use the picture in question 3.

   • 410.2 nm
   • 656.3 nm
   • 486.1 nm
6. 5.

   Starlight passes through cool hydrogen. Where do dark lines appear, Milo?

   • At hydrogen's own wavelengths
   • At random wavelengths
   • Spread across the whole spectrum
7. 6.

   What happens when an atom absorbs a photon of the right energy, Noah?

   • The nucleus splits
   • An electron jumps up a level
   • An electron drops down a level
8. 7.

   How do scientists learn what the Sun is made of, Pia?

   • From its size alone
   • From samples brought back from it
   • From the lines in its spectrum
9. 8.

   Which drop gives a bluer line: a big one or a small one, Ren?

   • A small one
   • A big one
   • Both give the same color
10. 9.

    Hydrogen's drop from n = 4 to n = 2 is compared with n = 3 to n = 2. Which line is bluer, Tala?

    • They match in color
    • The n = 4 to n = 2 line
    • The n = 3 to n = 2 line
11. 10.

    Drops to n = 1 in hydrogen give photons of 10 eV or more. What kind of light is that, Zee?

    • Ultraviolet
    • Infrared heat
    • Red