# Lecture 6: Flame Test and Bohr's Model

#### What is the flame test?

When supplying electric energy, a light glow is shown hydrogen structure. By the color we can tell the wave length, from the excess energy in the form of light.

### Bohr's Model

The atoms have to come back to the first level because it has the lowest potential energy (n=1). When they come back they release light (hydrogen specimen). All the lights produced when the atoms return to n=1 is called Lyman Ultra Violet. When they return to n=2 Balmer. When returning to n=3 this is called Paschen Infrared. The light we see in Hydrogen spectrum is Balmer. This is the light visible for us. The importance is where the atom goes and not where it comes from (n=2). How much energy? depends on the space between the levels ﻿$(E=n\frac{c}{\lambda })$﻿ ﻿$\lambda$﻿ changes - color changes. Lymann- highest energy, lowest wavelength-ultraviolet.

1. Ultraviolet - lowest wave length (Lymann) highest energy (returns to n=1)
2. Balmer - visible series (returns to n=2)
3. Infrared - highest wavelength (Paschen) lowest energy. (returns to n=3)

Energy ﻿$\uparrow$﻿ (J) ﻿$\lambda$﻿ ﻿$\downarrow$﻿ (nm)

﻿$E=n\frac{c}{\lambda }$﻿