Chemistry Mod 1 Flashcards
Structure of atoms
- Nucleus containing neutrons and protons
- Discrete electron shells containing electrons
Group (Periodic Table)
A column on the periodic table, where elements have the same valency and similar properties
Period (Periodic Table)
A row on the periodic table, where each element has the same number of electron shells
Atomic Number
The number of protons that an element has
Atomic Mass (Number)
The number of protons and neutrons that an element has
Isotope
Atoms of the same element that have different atomic mass numbers
Protium (Isotope)
A hydrogen isotope containing no neutrons
- Mass number: 1
Deuterium (Isotope)
A hydrogen isotope containing one neutron
- Mass number: 2
Tritium (Isotope)
A hydrogen isotope containing two neutrons
- Mass number: 3
Stable Isotope
An isotope that does not emit radiation and does not undergo spontaneous nuclear reaction
Unstable Isotope
Isotopes that undergo spontaneous reactions/decay naturally in order to try and return to stability
Relative Atomic Mass (RAM)
The average weight atomic mass of an atom, calculated using the mass number of its isotopes and its percentage abundance
John Dalton’s “Billiard Ball” model
All matter is made out of atoms, which are represented as an indestructible ball-like structure
J.J. Thomson’s “Plum Pudding” model
An atom consists of negatively-charged electrons and positively-charged protons, placed randomly in the atom’s ball structure
Ernest Rutherford’s Atomic model
An atom consists of negatively-charged electrons that orbit a positively-charged nucleus, which contains protons and neutrons
Niels Bohr’s Planetary model
In an atom, electrons orbit a nucleus (of protons and neutrons) in discrete shells with specific energy levels, where each shell can only hold a certain amount of electrons
Schrödinger’s Quantum model
The quantum model describes electrons as waves, where only the probability of finding an electron in a specific region can be determined, illustrated as orbitals
Bohr’s electronic configuration
The maximum number of electrons in an electron shell is denoted by 2n^2, where n is the energy level
Octet rule
Atoms prefer to have 8 electrons in their valence shell
