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Ch.12 - Solids and Solid-State Materials

Chapter 12, Problem 25

Diagrams (1) and (2) are energy-level diagrams for two different LEDs. One LED emits red light, and the other emits blue light. Which one emits red, and which blue? Explain. (1)

(2)

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Hello everyone today. We have the following problem energy level graphs for two distinct L E D. S are shown below and diagrams one into the one LED produces yellow light and the other LED produces violet light which produces yellow and which violet explained. So when it comes to LED lights which stands for light emitting diodes, there's a trend that the higher the energy the shorter the wavelength. So there's an inverse inversely proportionate relationship between these two. And we can also say that the smaller or the lower the energy the higher the wavelength. And so if we look at diagram one here, diagram one has a larger band gap energy than that of diagram too. And so we can say that this is going to emit blue light and this is going to emit red light on an electromagnetic spectrum red light tends to have a larger or a longer wavelength. So we already established that Diagram one has a larger band gap then diagram to. We can also conclude that diagram of one has higher energy and a shorter wavelength as a result. So it has a higher energy and a shorter wavelength on the electromagnetic spectrum violet is going to correspond with a shorter wavelength and yellow is going to correspond with a higher wavelength. And so therefore we can include that Diagram one is going to emit a violet light and Diagram two is going to admit yellow and so with that we have answered the question overall, I hope this helped. And until next time