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Luminol chemiluminescence

Chemicals: Sodium hydroxide, red blood salt, luminol , distilled water and hydrogen peroxide 30%

Procedure: prepare solutions A and B:

A-0, 1 g of luminol, 5 ml of 5% sodium hydroxide solution and make up to 400 ml with water.
B-1, 5 g of red blood salts, added to 400 ml of water and add 3 ml of 30% hydrogen peroxide.

After mixing the solution appears light blue luminescence. Especially significant is přilévání solution B to solution A funnel where it appears light melting solution

Luminescence - chemical equation

Oxygen chemiluminescence

Chemicals: Sodium hydroxide, 30% hydrogen peroxide solution, ice, chlorine is prepared by reaction of potassium permanganate and concentrated hydrochloric acid.

Procedure: In a ground flask is poured 5 g of potassium permanganate, and dropping funnel is added conc. hydrochloric acid, about 50 ml. The resulting chlorine is introduced into the washer with a solution of 20 g of sodium hydroxide dissolved in 40 ml of iced distilled water, which is cooled with ice, and about 160 g přilejeme 50 ml of 30% hydrogen peroxide. In a perfect blackout releasing oxygen solution dyed pink to red.

Cl 2 + 2NaOH -> NaClO + NaCl + H 2 O
H 2 O 2 + NaClO -> NaClO 2 + H 2 O
NaClO 2 -> * O 2 + NaCl

Oxygen colored substances in the environment  

Chemicals: luminol (in this experiment acts as an indicator), dichloromethane, sodium hydroxide, 30% hydrogen peroxide, chlorine is prepared by reaction of potassium permanganate and hydrochloric acid

Procedure: bubbler to dare 0.1 g of luminol, dissolve in 20 ml of dichloromethane, add 60 ml 6 M sodium hydroxide solution and after cooling, a solution of 20 ml 30 = hydrogen peroxide. When bubbling chlorine in the dark appears light chemiluminescence.

Luminescence of hydroquinone

Dissolving 1 g of hydroquinone, and 5 g of potassium carbonate in 40 ml of 30-40% aqueous formaldehyde (formalin). Pour the solution into the bottle with a volume of at least 1 liter (mixture foams). To this solution, add in a well darkened room 15 ml 30% hydrogen peroxide. The mixture starts to foam and an orange fluorescence.

The chemical energy is released by the oxidation of hydroquinone with hydrogen peroxide in an alkaline environment is almost completely converted to light energy by the heat and not, as is the usual reaction. Nevertheless, even in this reaction releases heat and formaldehyde starts to evaporate - attention is poisonous and odorless.

Luminescence in the crystallization

To 81.5 g of sodium sulfate (anhydrous) and 200 g of potassium sulphate are added in small portions with hot water. When the crystals are dissolved, let the solution cool freely. The first sparks can be seen in a darkened room already at 60 ° C, over time, creates the sparks bundles (about an hour). Fluorescence is caused by a chemical reaction

2K 2 SO 4 + Na 2 SO 4 + 10H 2 O -> 2K 2 SO 4thNa 2 SO 4 .10 H 2 O

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