Chapter 2 Flashcards
what are quantum numbers?
define the levels of electron orbitals
principal quantum number
n - always an integer (1,2,3…) - specifies shell of electrons and distance from nucleus
azimuthal number
l - specifies 3D shape of shell - (s,p,d,f or 0,1,2,3)
magnetic number
m(e) - defines number of electrons and orbitals in an atom - integer (+l or -l)
spin
m(s) - CW or CCW which in turn creates a moment so two electrons can be in almost the same space
valence electrons
electrons in outermost orbital - interact with other valence electrons to create bonds
what does having a full outermost shell mean?
the element is mostly inert/non-reactive
ionic bonds
electron transfer between two atoms to create full valence shells
cation
positively charged ion
anion
negatively charged ion
what are bond length and force decided by?
- interaction between the electron cloud and positive nucleus of adjacent atoms
- repulsive forces of negatively charged electron clouds
coordination number
governs characteristics/geometry of ionic bonds - depends on size of atoms (r/R) or (smaller atom radius/larger atom radius)
how to decide CN?
how many of atom A is touching one atom B
what is the max CN?
12
covalent bonds
electrons are shared between atoms
how do ionic and covalent bonds compare?
- similar bond energies and forces
- covalent bonds are directional while ionic bonds are not
for covalent bonds, the _________ is less important due to the sharing of electrons
size of atoms
metallic bonds vs ionic and covalent
non-directional like ionic but electron sharing like covalent
metallic bonds
create free moving and mobile electron cloud where electrons can move in any direction
secondary bonds (van der waals)
results from atomic or molecular dipoles when electron cloud is not uniformly distributed - creates asymmetry in bond or molecular shape
3 material structures
crystalline, polycrystalline, amorphous
