Term
|
Definition
| light that usually occurs at low temperatures and is thus a form of cold body radiation; it can be caused by chemical reactions, electrical energy, and subatomic motions. |
|
|
Term
|
Definition
| is heat-driven light emissions as a result of electron displacement. EX: light bulb |
|
|
Term
|
Definition
Electrons are initially at ground, stable energy state.
They become excited.
They move to a higher unstable energy state; electrons jump to outer orbital shells.
These valence electrons do not want to be in these outer orbital shells; prefer ground state orbitals.
So, they jump back to lower energy state orbitals.
This electron displacement emits energy in the form of visible light. |
|
|
Term
|
Definition
Triboluminescence
Chemiluminescence
Bioluminescence- |
|
|
Term
|
Definition
Triboluminescence is an optical phenomenon in which light is generated when material is pulled apart, ripped, scratched, crushed, or rubbed through the breaking of chemical bonds in the material.
For our experiment, it is caused by the separation and reunification of electrical charges. |
|
|
Term
|
Definition
Your group will receive both sugar and sugar free Wint-o-Green Life Savers®
Your group will use a set of pliers to crush the candy. Place the candy in your ziplock bag to avoid the candy from scattering.
Crush it in the dark and observe the faint blue sparks.
We hypothesize that the ones with sugar should produce the faint visible sparks.
Why?
Wint-o-Green Life Savers® contain SUCROSE.
During the crystallization process both + and - charges are separate. When you chew on them these charges come into close proximity which produces the sparks in your mouth. |
|
|
Term
|
Definition
Triboluminescence occurs when molecules, in this case crystalline sugars, are crushed, forcing some electrons out of their atomic fields.
These free electrons collide into nitrogen molecules in the air. When they collide, the electrons impart energy to the nitrogen molecules, causing them to vibrate.
In this excited state, and in order to get rid of the excess energy, these nitrogen molecules emit ultraviolet light.
This ultraviolet light fluoresces when it hits the wintogreen oil, (methyl salicylate), and produces the visible sparks. |
|
|
Term
|
Definition
Chemiluminescence is the emission of light as the result of a chemical reaction.
The chemical reaction will produce a bright blue light and no significant heat will be generated.
Luminol (C8H7N3O2)(reagent a, used in csi cuz it reacts with hemoglobin) + K4Fe(CN)63H2O (reagent b, poisonous, aka potassium ferriscyanide also aka potassium hexacyanoferrate) + H2O2 (hydrogen peroxide already added to reagent b) Oxidized Luminol + Blue light
H2O2 is the oxidizing agent and potassium hexacyanoferrate is the reducing agent. |
|
|
Term
|
Definition
OIL: Oxidation Is a Loss of electrons
RIG: Reduction Is a Gain of electrons
An atom that is itself oxidized is causing another atom or atoms to be reduced is called a reducing agent or reductant.
An atom that is itself reduced is causing another atom or atoms to be oxidized is called an oxidizing agent or oxidant. |
|
|
Term
|
Definition
EX: Fe + 2HCl FeCl2 + H2
Fe is the reducing agent; HCl is the oxidizing agent
FeCl2 is being oxidized and H2 is being reduced.
Oxidation: Fe Fe2+ + 2e-
Reduction: 2H+ + 2e- H2
Oxidation state of Fe changes from 0 to +2 (Cl- is unchanged)
These are called Redox or “half reactions” |
|
|
Term
| Manipulations of the Blue Light |
|
Definition
(2) Ways:
1. Diminish (quench) the light: adding HCl
2. Enhance the light: adding 1N NaOH
HCl shifts the reaction to the left, disfavoring the forward reaction and hence immediately quenching the light.
NaOH enhances the ability of the luminol to be oxidized by H2O2, so the reaction shifts to the right favoring oxidation and hence enhancing the light. |
|
|
Term
|
Definition
Objective: to determine composition of each dye.
Collect 3 test tubes: Follow the protocol
To tube 1 add reagents C, D and G
To tube 2 add reagents C, E and G
To tube 3 add reagents C, F and G
D, E and F are the unknown dyes:
1. Fluorescein (Yellow)
2. Rhodamine B (Rose)
3. Eosin Y (Orange)
C = luminol + DMSO (dimethylsulfoxide)
G = saturated NaOH(add one drop with Pasteur Pipette) |
|
|
Term
|
Definition
Bioluminescence is light that is carried out by living organisms. Ex: Firefly mating rituals
Lampyridae, (firefly), is a family of insects in the beetle order Coleoptera.
Commonly called “lightening bugs” for their conspicuous crepuscular use of bioluminescence to attract mates or prey.
Luciferin + O2 + ATP + Luciferase + Mg2+( the cofactor) Oxyluciferin (the oxyluciferin gets oxidized)+ AMP + PPi + H2O + Light
Luciferin comes from firefly lantern extract.
The cells of the firefly are called PHOTOCYTES! |
|
|
Term
|
Definition
Works at optimal pH = 7.4
Any shift in pH causes the visible light to quench
EX: 4N NaOH quenches the light; HCl has the same outcome
2% NaCl dims and eventually quenches the light. (time this part)
Why?
Chloride ions bind the Mg2+, so enzyme becomes catalytically inactive, (apoenzyme); reaction does not occur; so the light does not persist. |
|
|
Term
|
Definition
Divalent metal cations that must be present with the enzyme to make the enzyme catalytically active.
EX: Mg2+, Zn2+, Fe2+, Mn2+
Apoenzyme: enzyme without its cofactor.
Holoenzyme: enzyme with its cofactor. |
|
|
Term
| Luminescence in Marine Animals |
|
Definition
The deep-dwelling squid
Histioteuthis heteropsis is covered
with photophores, perhaps used to mask its silhouette from predators
and prey. |
|
|
Term
| Luminescence in Marine Animals |
|
Definition
| The polychaete Tomopteris is one of the only marine creatures that makes yellow luminescence. When disturbed, a flurry of glowing sparks will erupt from the parapodia (the paddle-like structures). |
|
|
Term
|
Definition
Luminol is used by forensic investigators to detect trace amounts of blood left at crime scenes as it reacts with iron found in hemoglobin.
It is also used by biologists in cellular assays for the detection of copper, iron, and cyanides. |
|
|
