1. BOHR’S ATOM AND ATOMIC SPECTRA
UNIT #2 THE ATOM

2. Background
A hydrogen atom consists of one proton (positively charged particle) and one electron (negatively charged particle)
Generic diagram:

3. Atomic Spectrum of Hydrogen
When hydrogen gas is excited (given energy) and then this energy is released, only light with specific wavelengths are emitted
Called a “line spectrum”

4. Continuous Spectrum

5. Significance of Line Spectrum
All elements and compounds have unique line spectrums which are different from each other
The line spectrum was actually a huge clue into the discovering the structure of the atom

6. Bohr’s Hydrogen Atom Model
Often referred to as the “planetary model”

7. Bohr’s Equation for the Hydrogen Atom
E = x J ( 𝑍 2 𝑛 2 )

8. Practice Problem
Calculate the amount of energy that is released when an electron in hydrogen travels from energy level three to the ground state. Then, find its wavelength.

10. Last Note… Absorption spectrum – spectrum of what an atom will absorb
Emission spectrum – spectrum of what an atom will emit
Spectrometer – machine which helps determine absorption and emission spectrums of different elements and compounds