Zusammenfassung der Ressource
Arrangement of electrons in the Atom.
- Bohrs study of spectra
- light passed
through a prism,
broken up into an
array of colours
called a spectrum
- light from a hydrogen discharge
tube, Niels Bohr found that
instead of seeing a continuous
spectrum, he saw a series of
narrow lines called an emission
line spectrum
- each element
has its own
unique
emission line
spectrum.
- Flame test
- Explaining the evidence of the Bohr theory
- 1) electrons revolve around
the nucleus in fixed paths
called orbits.
- 2) electrons
have fixed
amount of
energy. for this
reason they are
called energy
levels.
- An energy
level is defined
as the fixed
amount of
energy value
that an electron
in an atom may
have.
- 3)as long as
an electron is
in any one
particular
energy level it
neither gains
nor loses
energy
- when an atom
absorbs
energy, it
jumps from a
lower energy
level to a
higher energy
level.
- energy is lost when an electron
falls from a higher energy level to
a lower energy level.
- Quantisation
- the energy of an electron in a particular energy
level cannot have just any value but may only
have a certain specific value
- energy levels = n
- E = hf
- E- definite
amount of
energy
emitted
from atom
- hf = light of definite
frequency or
wavelength in
emission spectrum
- every element has its own unique arrangement and number of electrons
giving rise to its own unique set of energy transitions thus its own unique
spectrum.
- atomic absorption spectrometry
- atoms can absorb light.
- an absorption spectrum is produced when white light
is passed through a gaseous sample of an element, it
consists of dark lines against a coloured background.
- wave nature of an electron.
- Louis de Broglie stated
that electrons do not
travel in a fixed path, it
has a wave motion.
- Werner Heisenberg.
- Heisenbergs
uncertainty principle
states that it is
impossible to measure
the velocity and
position of the electron
at the same time.
- an orbital is a region in
space within which there
is a high probability of
finding an electron.
- Erwin Schrodinger
- Schrodingers equations were solved to give us the shapes of the 4 orbitals S,P,D,F
- All S orbitals are
spherical and only
differ in size.
- P orbitals are dumbbell
shaped. the three parts
are Px, Py, and Pz