Light Producing Chemical Reactions
Matthew Landry CHEM 1202 – General Chemistry II
Spring Intersession 2012
What is Light?
• The natural agent that stimulates sight and makes things visible
• Electromagnetic radiation from about 390
to 740 nm in wavelength.
Part I: Chemiluminescence
• Certain organic chemical reactions can produce light either by luminescence or phosphorescence.
• Firefly • Chemical reactions that release energy that is efficiently converted to light, but almost no heat.
Part II: Quantum Fireballs
• Lithium (Li) • Sodium (Na) • Potassium (K) • Calcium (Ca) • Strontium (Sr) • Copper (Cu)
• Fireworks and Pyrotechnics
Part II: Quantum Fireballs
• General Reaction M+n ion + Heat Energy à {M+n excited state} à M+n + Light Emitted
Part II: Quantum Fireballs
Each metal has its own light emission profile, due to the differences of electron orbital energies unique to that element.
Part III: Burning Mg in CO2
• Fire extinguishers • The heat produced by this reaction
which begins in the open atmosphere is sufficient to decompose the CO2.
Mg(s) + CO2 à MgO (s) + C(s)