Emission

longer

Emitted light has a __________ wavelength than absorbed light.

Relaxation

Losing energy; trying to go to the ground state

do not, ground, conserved

Molecules __________ remain excited (because at some point, does not reach a certain amount of discrete level of energy, so must go down to __________state) - Energy must be __________

Fluorescence

Molecules can lose energy by emitting light in a process called ____________ - does not give off photons

emit, slow

The easiest way for a molecule to dissipate (disappear) excess energy is to _______heat and ________ its vibrations

ground

The energy of photon goes to the ________ state in Fluorescence process

decomposition, dioxane, gernerates

The reaction in glow sticks is driven by the rapid ____________ of the "_________" to carbon dioxide (A+B --> C* + D) which ___________ a lot of energy - breaking off of Carbon and Oxygen (dioxane), ___________more energy

Luminescence

This "relaxation" via emission of light is known generally as _____________

Emission

When molecules of light relax to the ground state, gives off energy.

Bioluminescence

_____________ and Chemilunesene need some chemical reaction that causes light

Luminescence

- Transmission can only be detected directly in line with the incident light. - ___________can be detected in all directions - Emitted wavelengths often dominate the light observed - general term for glowing

emit

After molecules absorb light and become excited, they can _______ light to return to the ground state

reverse, slow

After vibrational relaxation occurs, finally the molecules return to ground state and the molecules must "________their spin" again making this another __________ process.

reverses, intersystem crossing, slowly

Alternatively, one of the electrons in the molecule "__________ its spin" causing a slight change in energy in _________________ stage - This is very hard and therefore occurs very __________

Bioluminescence, luciferase

Defined as the emission of light as a result of a biological reaction - ex. Firefly Luciferin ---Luciferin + O2 ---> Oxyluciferin + yellow light ---The reaction is catalyzed by an enzyme called ___________ ---The light emission step is very similar to that in a glow stick! ---The light emission step again involves the rapid release of CO2 and generation of energy - another ex. Crystal jellyfish

Chemilumenscence

Defined as the emission of light due to a chemical reaction. - A and B react to form an excited product C, then C relaxes to ground state. Because the product C has a different energy from the reactants, A and B, energy is emitted as light --- so as reaction starts, relaxation emits light (giving off energy), which creates a glow (or luminescence) - ex. glow sticks (must explain this) - light is given off not heat!

Phosperescence

Fluorescence and ____________ need light to see excitation

longer, rapidly

Fluorescence occurs when while the light source is present to excite molecules. - Giving off ________ wavelengths of light - Shut off the light, don't see it, it's over - happens easily and ____________

Emission follows absorption

How does emission happen?

bluer

If you cannot differentiate the ripeness by the color of the banana (cause you are blind) use your feel, sense of smell to figure it out. - since Fruit bats are colorblind and bananas absorb UV light and give off blue light, can detect if the banana is ripe by looking at the blue light. - the _________they are, the riper they are

Fluorescence

__________________ occurs when while the light source is present to excite molecules - ex. glow-in-the-dark-stickers - if you dissolve fluorescein in water and put it under black light, will look green (absorbs cyan, observes orange/red) - since tonic water contains quinine, if you put a UV light over it, it glows

no light

____________is emitted during a vibrational relaxation