Bohr's Model

(1) Explain Bohr’s Model and how it accounted for the hydrogen emission spectrum.

Bohr’s Model of the Atom

Electron Orbit

Ground State: orbit closests to the nucelues (n=1). Excited State: orbit further away from the nucleus (n=2,3,4,5,6,7).

Bohr’s model says that electrons can only exist in certain orbits around the nucleus. These orbits are quantized, so only certain orbits are allowed. Electrons can jump between these orbits by absorbing or emitting energy.

Electron Jumps

When an electron jumps from an outer orbit to an inner orbit, it emits energy in the form of light. However, when an electron jumps from an inner orbit to an outer orbit, it absorbs energy.

Hydrogen Emission Spectrum

• When an electron jumps from a higher energy level to a lower energy level, it emits energy in the form of light.
• This light is called an emission spectrum.
• The hydrogen emission spectrum consists of four lines in the visible region of the electromagnetic spectrum.
• These lines are called the Balmer series.
• Different colors of light are emitted depending on the energy difference between the two energy levels, which accounts for the light’s wavelengths.

Caution

Bohr’s model only works for hydrogen-like atoms (atoms with only one electron). It does not work for atoms with more than one electron. It is also only a qualitative method of understanding an atom.