Chemistry Flashcards
study (53 cards)
atomic model; the atom is hard and indestructible
Billiard Ball Model (John Dalton)
atomic model; electrons are embedded in a positively-charged sphere
Plum Pudding Model (JJ Thompson)
atomic model; the mass and all of the positive charge of an atom are concentrated on the nucleus
Nucleus Model (Ernest Rutherford)
atomic model; electrons travel around the nucleus in a circular orbit; their energy is proportional to their distance from the nucleus
Planetary Model (Niels Bohr)
atomic model; the electron is a wave (found in orbitals)
Quantum Model
5 atomic models
- Billiard Ball
- Plum Pudding
- Nuclear
- Planetary/Bohr
- Quantum
number of protons in the nucleus; also equal to the number of electrons
atomic number
protons + neutrons
mass number
True or False: in an atom, the number of protons is constant
True
The Atomic Theory
- all matter are made up of atoms
- all atoms of an element have identical chemical and physical properties
- atoms of different elements have different sets of chemical and physical properties
atoms of the same element that differ in the number of neutrons
isotopes
highly reactive metals
alkali metals
highly reactive non-metals
halogens
inert gases, highly stable elements
noble gases
charged atom
ion
negatively charged ion; gain in electrons
anion
positively charged ion; loss in electrons
cation
energy required to remove an electron from an atom
ionization energy
energy released when an electron is added to an atom
electron affinity
ability to attract electrons
electronegativity
4 Quantum numbers
- principal
- azimuthal
- magnetic
- spin
the number of excess electrons of an atom
valence electrons
every element has the same electronic configuration as the element before it in the periodic table, plus one extra
Aufbau Principle
electrons tend to stay unpaired in orbitals with equal energies
Hund’s Rule
