Flame test lab

Potassium

Purple ; 420 nm/4.2 x 10^-7 m

Lithium

Red ; 660 nm/6.6 x 10^-7 m

What causes the different colors?

The different energy levels of each metal. They are different due to the different energy levels each element has. Light is produced when electrons move back to their original(ground state) because a photon is released. Each have different wavelengths that cause different colors.

What has the highest energy and what has the lowest? What's a trend?

Blue has the highest while red has the lowest. Low energy are typically at the top of the periodic table while high is at the bottom.

What are possible sources of error?

Contamination could have complicated the identification of elements and thus lead to inaccurate results. It would've emitted a different color and lead to the wrong identification. Also the stirring rod could have been contaminated or the solution could have reacted with the oxygen in the air and changed in the case of potassium.

Copper

Green ; 525 nm/5.25 x 10^-7 m

What do elements with low energy photons have?

Lower energy levels so they are located on the first couple of periods on the periodic table.

Calcium

Orange ; 620 nm/6.2 x 10^-7 m

Sodium

Orange ; 620 nm/6.2 x 10^-7 m

Purpose?

To learn about how the relationship between light and energy of metals. Different metals give off different colors due to different energy levels. Energy can be found with E=(Planck's constant X speed of light) /wavelength. Light is emitted one the electrons move back to a lower energy level due to loss of the energy required to remain in the high energy level.

What were the unknown and how did you know?

Unknown A is lithium because it emitted red light and lithium is known to emit red light. Unknown B is potassium because it emitted purple light and that is what potassium is supposed to emit.

Lead

White ; 283 nm/2.83 x 10^-7 m