E.1 - Structure of the atom Flashcards
How was Rutherford’s gold foil experiment conducted?
Alpha particles were fired at gold foil.
What were the results of Rutherford’s gold foil experiment?
Most particles were undeflected; certain particles were deflected at small angles and others were deflected at large angles
What were the conclusions?
Undeflected: the atom is mostly empty space. Small angles: passed near the nucleus and got repelled. Large angles: Same thing but passed very near the nucleus.
What is the number of alpha particles after deflection depend upon?
the scattering angle. The greater the angle, the fewer are detected.
The number of alpha particles observed also depends upon the _
energy
What is the distance of approach?
The minimum distance of a charged particle from the center of a nucleus where the kinetic energy of the particle is transferred to the electric potential energy of the system.
Formula for distance of approach?
d = k(2xZe^2/E)
What is the radius of a nucleus formula?
R = R0 A^1/3
Since electrons can only orbit a nucleus at discrete distances, atoms have a set of discrete _ _.
energy levels
What is an atomic transition?
The movement of an electron from one energy level to the other. L->H is excitation, H-> L is de-excitation
Near the nucleus, the energy level is _.
lowest
Since energy levels are discrete, the _ emitted is also discrete. The _ is emitted in the form of _s.
energy, photon
Formula for energy of a photon?
E = hf
If a _ gas particle is excited, it will emit _. The _s emitted have specific _. Hence a _ will be formed.
hydrogen, photon, photon, energies, spectrum
if light is shined at _ gas, an _ _ is formed.
hydrogen, absorption spectrum
