Unit 2: Matter and Chemical Bonding Flashcards
Subatomic particles
Protons: P^+ - in nucleus, mass = 1 (= to atomic #)
Neutrons: n^0 - in nucleus, mass - 1 (atomic mass - atomic #)
Electrons: e^ - in orbitals, mass = 0 (= to atomic #)
Isotopes
elements that have atoms which differ by the number of neutrons
Hydrogen issotopes
Protium 1
Deutrerium 2
Tritium 3
Radioissotope
Nucleus decays
Atmoic mass
a mass for one atom of an element based on the weighted averageof all mass #s of the issotopes
AM = (MNa x%A + MNb x%b etc)/100
Ion
An atom with an electrical charge because it lost or gained electrons
Reacticity
a measure of how likely a substance is to be involved in a chem reaction
F is lowest Fr is most reactive
Atomic radius
a measure of the size of the atom
down = bigger
left = smaller
Ionic radius
Metal ions are smaller than metal atoms, metals want to have a full shell so they gain electrons
First ionization energy
the amount of energy required to remove an electron from an atom,
Fr lowest F highest +noble gasses
Coulombs law
the attraction between opposite charges decreases with increased distance between them
Electronaffinity
(gaining electrons) ability to capture electrons
Measured in KJ/mol
F is highest and Fr and noble gases lowest
Electronegativity
ability to capture electrons but measured on a scale from 0-4
Fr is highest
F is lowest
Molecules
Created by atoms joining together into larger particles
law of definite proportions
The molecules of a compound alwaus have the same number of each type of atom
ex,. h20 always has 2 hydrogen atoms and 1 oxygen
Ionic bond
transfer of electrons between atoms
Covalent/molecular bond
sharing electrons between atoms
EN scale
0-0.5 non-polar covalent
0.5-1.7 polar covalent (uneven sharing)
1.7-4 ionic bond
Intramolecular forces
forces within a molecule that hold it together
ex. non-polar covalent, polar covalent, ionic
Intermolecular forces
attraction between molecules
3 main considerations:
-polarity of molecules
-size of molecules
-shape of molecules
London forces
(size) substances with larger molecules have more attraction to each other than smaller molecules (attraction based on molecule size)
Dipole-dipole
attraction based on polarityHy
Hydrogen bond
technically not a bond but attraction
a strong dipole dipole attraction
occurs between molecules that have an H bonded to O, N, or F
Ionic crystal lattice
how they connect, most solid pure substances are in this form
