The Hydrogen Spectra and Bohr's Theory Flashcards
Explain Bohr’s Atomic Model
- electrons in hydrogen atom orbits circularly around nucleus due to coulomb attraction to nucleus
- electrons can only orbit in certain orbits
- electrons can transition from a orbit to lower orbit by emitting a single photon whose energy is equal to difference in energy between the two states
Summarise Bohh’rs atomic model of a hydrogen atom
Electrons can only exist in specific orbits around nucleus. These orbits are charaterised by quantised energy ststaes. Electrons transition from a higher to a lower energy state by emitting a single proton, where its energy is equal to difference between energy states.
Describe attributes of Lyman Series
When electron falls to n=1, the first energy state. Ultraviolet spectrum
Describe attributes of Balmer Series
When electron falls to n=2, the second energy states. Visible spectrum
Describe attributes of Paschen Series
When electron falls to n=3, the third energy states. Infrared spectrum
What value can n have?
any whole number greater than 0, as there are infinited energy states
What is the GROUND STATE?
When n=1, as electron in hydrogen atom at this orbit has lowest possible energy.
What is EXCITED STATE?
When n is greater than 1, or when electron is above ground state. Electron in excited state transitions to ground state by losing energy through emtiting a photon, which its energy is equal to the difference in E of the 2 states.
What is EXCITATION ENERGY?
the energy provided/required to atom that causes an electron to transition from a LOW to a HIGH energy state
Why do scientists believe that energy levels are quantised?
because the observation of only a few values of wavelength in the line spectrum meant that only a few values of E were possible. Thus energy levels of hydrogen had to be quantised.
What does n= infinity mean?
means that energy holding electron and nucleus together is 0. Process is called ionisation
