Quantum Theory
Quantum Mechanics is abranch of
mathematical physics that deals with the
emission and absorption of energy by
matter and with the motion of material
particles. Because it holds that
energy and matter exist in tiny, discrete
amounts, quantum mechanics is
particularly applicable to Elamentry Pprticlesand
the interactions between
them. According to the older theories of classical
physics, energy is treated
solely as a continuous phenomenon and matter is
assumed to occupy a very
specific region of space and to move in a continuous
manner. According to the
quantum theory, energy is emitted and absorbed in a
small packet, called a
quantum (pl. quanta), which in some situations behaves as
particles of matter
do; particles exhibit certain wavelike properties when in
motion and are no
longer viewed as localized in a given region but as spread out
to some
degree. The quantum theory thus proposes a dual nature for both waves
and
particles, with one aspect predominating in some situations and the
other
predominating in other situations. Quantum mechanics is needed to
explain many
properties of matter, such as the temperature dependence of the
specific heat of
solids, as well as when very small quantities of matter or
energy are involved,
as in the interaction of elementary particles and
fields, but the theory of
Relativity assumes importance in the special
situation where very large speeds
are involved. Together they form the
theoretical basis of modern physics. (The
results of classical physics
approximate those of quantum mechanics for large
scale events and those of
relativity when ordinary speeds are involved.) Quantum
theory was developed
principally over a period of thirty years. The first
contribution was the
explanation of blackbody radiation in 1900 by Max Planck,
who proposed that
the energies of any harmonic oscillator, such as the atoms of
a blackbody
radiator, are restricted to certain values, each of which is an
integral
(whole number) multiple of a basic minimum value. Over the years there
has
been a number of models that were supposed to have been atomicly
correct.
Right now we are currently useing the Schrodinger model to show
the atomic
structure of an atom. There also was other models of the atomic
structure of an
atom but they were wrong. They were wrong because at those
times there was not
enough tecknoladgy around to ptove other wise. The names
of the major noted
scientists that had made a model of the atomic structure
of an atom, are Bohr,
Rutherford, Thompsom, and Schrodinger. The current
atomic theory is that
Schrodinger and the other scientists abandoned the
idea of precise orbits, and
replaced it with a discription regions called
orbitals. We have been useing that
same theory for almost eighty years now
and it looks like we are not going to
change it still. Shrodinger's modelwas
basically a cloud of sub atomic particles
in orbit around a nucleus. The
electrons moved in orbit around the nucleus but
also moved in tiny orbitals.
These orbitals are revolutions around possibly
another subatomic particle
while in orbit around the nucleus which is holding
protons, neutrons, and
other sub atomic particles. Another scientist that
created a model of the
atomic structure of an atom was Rutherford. His model was
an model in which
the the atom was held together by an electrical attraction
between the
nucleus and the electrons. by electrical attraction between the
nucleus and
the electrons. In this model the electrons travelled in relatively
distant
orbits around the nucleus. The model eventually proved successful in
of
chemistry and everyday physics. Subsequent studies of the atom divided
into
investigations of the electronic parts of the atom, which came to be
known as
atomic physics, and investigations of the nucleus itself, which came
to be known
as nuclear physics. His experiment: He studied hydrogen by
hitting it with
electricity. The electricity would excite an electron anc
cause it to jump to
higher energy levels. When it fell back down, a photon
was given off. The photon
of light corresponded with the amount of energy per
energy level. Other
scientist also made models that had an impact on the
scientific community. One
of them is Rutherford. In 1898, Rutherford obtained
the physics professorship at
McGill University, Montreal. Rutherford
proposed an atomic model in which the
atom was held together by electrical
attraction between the nucleus and the
electrons. In this model the electrons
travelled in relatively distant orbits
around the nucleus. The model
eventually proved successful in explaining most of
the phenomena of chemistry
and everyday physics. Subsequent studies of the atom
divided into
investigations of the electronic parts of the atom, which came to
be known as
atomic physics, and investigations of the nucleus itself, which came
to be
known as nuclear physics. His experiment: His experiment was that
he
bumbarded a sheet of gold foil with alpha particles, and discovered that
the
atom was not a solid mass, but infact is made soly of empty space.
Another
scientist that made a break through in the current model of the
atomic structure
of an atom was known as Thompson. In 1895, Thomson
discovered the electron. His
evidence came from the experiment he did using
an apparatus that allowed him to
see the glow of the stream of negatively
charged particals released when a gas
is subjected to intense electrical
forces. These particals are known now to be
electrons. It was his experiments
that proved that the atom was not an
indivisible particle. Instead, it was
made up of different particles itself. In
1906, Thomson recieved a nobel
prize for his discovories. Thomson's model of an
atom was a solid sphere with
electrons embedded in the positive part of the
atom. The positive part of the
atom makes up the bulk of the atom's mass and
volume. It was hypothesized
that the positive part of the atom was fluid. John
Dalton was a english
scientist. He taught mathematics and physical sciences at
New College,
Manchester. Dalton revived the atomic theory of matter which he
applied to a
table of atomic weights and used in developing his law of partial
pressures.
He was color-blind and studied that affliction, also known as
Daltonism.