Atomic Flashcards
Coined the word atom
Democritus
Proposed the Atomic theory
John Dalton
- Elements are composed of tiny indivisible particles called atoms
- Atoms of different elements are chemically different; however atoms of a given element are of the same size, shape, mass and chemical properties
Atomic Theory
Proposed the “Law of Conservation of Mass”
Antoine Lavoiser
“A chemical reaction only involves separation, combination or rearragement of atoms”
Law of Conservation of Mass
Proposed the “Law of Multiple Proportions”
John Dalton
“When two elements combine with each other to form two or more compounds, the ratios of the masses of one element that combines with the fixed mass of the other are simple whole number ratios”
Law of Multiple Proportions
Proposed the “Law of Definite Proportions”
Joseph Proust
“A given chemical compound always contains the same elements in the exact same proportions by mass”
Law of Definite Proportions
Discovered the negatively-charged particles, electrons
Joseph John Thompson
Used to determine the electrons
Cathode Ray Tube
Suggested the Plum-Pudding Model
Joseph John Thompson
Determined the ratio of the electric charge to the mass of an electron to be -1.76x10¹¹ C/kg
Joseph John Thompson
Gave the name electron
George Johnstone Stoney
Determined the mass of an electron
Robert Millikan
Used to determine the mass of an electron
Oil drop experiment
Discovered the positively-charged particles, protons
Eugene Goldstein
Used to determine the protons
Anode Ray Tube
Discovered neutron by bombarding Be with alpha particles. These particles are not affected by electric field
James Chadwick
Discovered nucleus by performing Goild foil experiment wherein a thin foil of gold is bombarded with alpha particles
Ernest Rutherford
Is a phenomenon where electrons are emitted from the metal surface when the light of sufficient frequency is incident upon
Photoelectric effect
Basis for solar panels
Photoelectric effect
Is the minimum energy required to remove an electeon from the surface of the material
Work function
1 eV = ___ J
1.6x10‐¹⁹ J
1 kWh = ____ MJ
3.6
Scattering of a photon by a charged particle, usually an electron
Compton Scattering
Matter might also exhibit wave-like properties under suitable conditions
De Broglie Wavelength
It states that “Any hot vibrating body does not emit nor absorb energy continuously, but discontinuously, in the form of small packets of quanta”
The Quantum Theory of Atoms
It states that “ It is impossible to know exactly both the position and momentum of an electron or any other small particle simultaneously and accurately”
Heisenberg Uncertainty Principle
It states that “Electrons behave as particles and waves”
Wave - particle duality
It states that “Electrons revolved around the nucleus in elliptical orbits with different eccentricities of which Bohr’s circular is a special case”
Bohr -Sommerfield Theory
Concluded that electrons behave more like waves than particles
Davisson - Germer Experiment
The region in space around the nucleus where it is most probable to find an electron
Orbital
Tells the
- Distance of an electron from the nucleus
- Energy of an electron in the orbit (energy levels)
Principal Quantum Number
True or False
The larger the value ofthe principal quantum number, the farther is the electron from the nucleus
TRUE
Tells the
- Shape of orbital
- Subshell position of electron
Azimuthal / Angular Quantum Numbers
Tells about
- Orientation of orbitals in space
Magnetic Quantum Number
Shows the spin of electrons
Spin Quantum Number
Aufbau means
Filling up
States that “the orbitals must be filled up in increasing energy levels”
Aufbau Principle
States that “No two electrons in an atom can have the same set of quantum numbers and an atomic orbital must contain a maximum of two electrons with opposite spins”
Pauli’s Exclusion Principle
States that
- The pairing up of electrons in an orbital of a subshell takes place only when all orbitals contain atleast on electron
- The most stable arrangement of electrons in subshells is the one with more parallel spins
Hund’s Rule of Maximum Multiplicity
States that “The stablest structure is the one with carbon atom that has formal charge near to zero”
Kekule Rule of Resonance
The hydrogen emission lines associated with the visible part of the spectrum is called the ____ series
Balmer
The hydrogen emission lines associated with the ultraviolet part of the spectrum is called the
Lyman
The hydrogen emission lines associated with the infrared part of the spectrum is called the _____ series
Paschen
