Luminol

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Research Question 1: What is the effect of varying concentrations of luminol (1%, 2%, 3%, 4% and 5% w/v) on the oxidation of luminol when reacted with sodium hypochlorite (3%) as measured through change in light intensity (lx)? Research Question 2: What is the effect of varying temperatures (0, 20, 40, 60 and 80) in kelvin on the oxidation reaction between luminol and sodium hypochlorite measured through the change in light intensity (in lx) in order to determine activation energy of the reaction? Hypothesis: As concentration of luminol increases, the amount of light intensity produced will also increase. At 5% luminol, brightest light intensity will be recorded as a result of most frequent collisions. An increase in temperature will increase …show more content…

In such cases, oxidation refers to the loss of electrons and reduction refers to the gain of electrons by molecules, atoms and ions. Redox reactions, always involve the simultaneous oxidation of one reactant with the reduction of another as electrons are transferred between them3. The reactant that accepts the electrons is called the oxidizing agent. In the process of bringing about oxidation, it becomes reduced3. The other reactant that supplies the electrons is known as the reducing agent. In the process of bringing out reduction, it becomes oxidised3. Luminol (5- Amino-2,3-dihydro-1,4-phthalazinedione)4 is a chemical compound that contains amine groups, two carbonyl group and multiple double bonds (C8H7N3O3). It has a yellow crystalline structure and it is soluble in suitable solvents but it is insoluble in water4. When luminol is reacted with an appropriate oxidizing agent, it is reduced and in the process it produces a blue …show more content…

At this point, the compounds are at an electronically stable position at equilibrium. When solutions containing ClO- ions such as sodium hypochlorite are added, there occurs a collision between these ions and the dianion of luminol and hence a transition state is reached5. At the transition state, the intermediate has high energy and electrons are seen to be in an excited electronic state5. Henceforth, the electrons move to a higher energy level which makes them unstable and the electrons of the high-energy intermediate are seen to fall back to ground energy. In the process, photons of light are emitted5. In this case, the unit of illuminance is represented in lux, which measures as luminous flux per unit

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