part 2 Flashcards
coined the term “atomos”
atoms were uniform, solid, hard,
incompressible, indestructible. and
that they moved in infinite
numbers through empty space
until stopped.
DEMOCRITUS - Democritus was an Ancient Greek pre-Socratic philosopher primarily remembered today for his formulation of an atomic theory of the universe. Democritus was born in Abdera, Thrace, around 460 BC, although there are disagreements about the exact year.
Billiard Ball Model Matter is made up of atoms
All atoms of a given element are
alike Atoms enter into a combination
with other atoms to form
compound but remain unchanged
during ordinary chemical reaction. Atom can combine into simple
numerical ratios
JOHN DALTON (1803) - john Dalton FRS was an English chemist, physicist and meteorologist. He is best known for introducing the atomic theory into chemistry,
Raisin Bread Model
Its shows the atom as composed of
electrons scattered throughout a
spherical cloud of positive charge
No nucleus, didn’t explain later
experimental observations
Discovered electrons
J. J. THOMPSON (1904) - suggested a model of the atom, hypothesizing that it was a sphere of positive matter within which electrostatic forces determined the positioning of the corpuscles.
Gold Foil Experiment
Atom is mostly an empty space with
positive charge concentrated in the
center
ERNEST RUTHERFORD (1911) - Rutherford discovered the atomic nucleus, using a “scattering” experiment, diagramed at right, that would become a classic technique of particle physics.
Planetary Model
Electrons moved around the nucleus in
orbits of fixed sized and energies
NIELS BOHR (1913) - In 1913, Niels Bohr proposed a theory for the hydrogen atom, based on quantum theory that some physical quantities only take discrete values.
Quantum Mechanical Model
He stated that electrons do not move in
set paths around the nucleus, but in
waves.
“clouds of probability”
ERWIN SCHRODINGER - Schrodinger discovered one of the foundations of quantum mechanics,
equal to electrons
equal to the atomic number
PROTONS - is a subatomic particle found in the nucleus of every atom.
mass number - atomic number and uncharged
NEUTRONS - is a subatomic particle found in the nucleus of every atom except that of simple hydrogen
equal to the atomic number , protons charged
ELECTRONS - a negatively charged subatomic particle that can be either bound to an atom or free (not bound).
FIND PROTON
The number of protons in the nucleus of the atom is equal to the atomic number (Z).
ISOTOPE SYMBOLS
A- MASS NUMBER, PROTON + NEUTRONS
X- ELEMENT
Z - ATOMIC NUMBER
FIND NEUTRON
The number of neutrons in an atom can be calculated by subtracting the atomic number from the atomic mass
FIND ELECTRON
The number of electrons in an atom is equal to the atomic number of an element, for neutrally charged species
determines the size of particle, n ,123
PRINCIPAL
DETERMINE THE SHAPE S,P,D,F. VALUE IS EQUAL TO THE TOTAL NUMBER OF ANGUALR NODES IN THE ORBITAL. I . 0 TO (N-1)
AZIMUTHAL
DETERMINE THE ORIENTATION M OR ML -1 TO +1
MAGNETIC
GIVES INSIGHT TO THE DIRECTION OF THE SPIN OR ROTATION. S OR MS -1/2 OR +1/2
ELECTRON SPIN
no electrons can have
the same set of 4
quantum numbers
PAULI’S
EXCLUSION
PRINCIPLE
the e-momentum and
position is impossible to
determine simultaneously.
HEISENBERG’S
UNCERTAINTY
PRINCIPLE
lower energy levels are
filled up first
AUFBAU PRINCIPLE
Orbitals are filled up singly
before pairing up
HUND’S RULE OF
MAXIMUM MULTIPLICITY
tried grouping the elements as non metals
ANTOINE LAVOISIER(1789) - was a French nobleman and chemist who was central to the 18th-century chemical revolution and who had a large influence on both the history of chemistry and the history of biology.
he arranged the elements
in groups of three in
increasing order of atomic
weight and called them
“triads”
.
JOHANN
WOLFGANG - was a German poet, playwright, novelist, scientist, statesman, theatre director, and critic. His works include plays, poetry, literature, and aesthetic criticism as well as treatises on botany, anatomy, and colour.
created the framework that
became the modern periodic
table. predicted the properties of
some undiscovered elements
and gave them names such
as “eka-aluminum”
DMITRI
MENDELEEV - a Russian chemist and inventor. He is best known for formulating the Periodic Law and creating a version of the periodic table of elements.
produced a version of the periodic table similar to mendeleev in 1870
LOTHAR MEYER - German chemist. He was one of the pioneers in developing the earliest versions of the periodic table of the chemical elements
ARRANGE ELEMENTS ARRANGE ACCORDING TO ATOMIC NUMBERS
HENRY MOSLEY as an English physicist, whose contribution to the science of physics was the justification from physical laws of the previous empirical and chemical concept of the atomic number.
ELEMENTS ARE ARRANGE ACCORDING TO ATOMIC NUMBERS
HENRY MOSLEY as an English physicist, whose contribution to the science of physics was the justification from physical laws of the previous empirical and chemical concept of the atomic number.
