Chem unit 7 Flashcards
covalent bonds…
involve a SHARING of electrons
NM and NM
as atoms move closer, potential energy decreases/increases
decreases
ionic bonds
involves a TRANSFER/attraction of electrons
M and NM/cation –> anion
metals have the tendency to _____ electrons
lose
nonmetals have the tendency to ____ electrons
GAIN
What is an ionic crystal
forms when multiple ion pairs are attracted to eachother
TRUE/FALSE- ionic compounds must have two pos ions to form
FALSE- must have one pos and one neg
lower in energy =
more stable (covalent bonds)
exceptions to octet rule
H- 2 ve
Be- 4 ve
B- 6 ve
third period and below can have 8+ ve
2,2,0
molecular geo - linear
e geo- linear
3, 3, 0
e/molec - trigonal planar
3, 2, 1
e- trigonal planar
m- bent
TEP = 2
linear
180 degrees
TEP = 3
e geo - trigonal planar
120 degrees
TEP = 4
e geo- tetrahedral
109.5 degrees
TEP = 5
e geo- trigonal bipyramidal
degrees vary
TEP = 6
e geo- octahedral
90 degrees
4, 4, 0
e/molec- tetrahedral
4, 3, 1
e-geo = tetrahedral
molec geo- trigonal pyramidal
4, 2, 2
e geo- tetrahedral
molec- bent
5, 5, 0
e/molec- trigonal bypyramidal
5, 4, 1
e geo- trigonal bypyramidal
molec geo- seesaw
120/90 degrees
5, 3, 2,
e geo- trigonal bipyramidal
molec geo- T-shaped
90 degrees
5, 2, 3
e geo- trigonal bipyramidal
molec- linear
180 degrees
examples of e-geometry
linear, trigonal planar, tetrahedral, trigonal bipyramidal, octahedral
examples of molec geo
(electron geo) + bent, seesaw, T-shaped, square pyramidal, square planar, trigonal pyramidal
0.4 and below
nonpolar
above 0.4 - 1.7
polar
above 1.7
ionic
polar molecule
-assymetrical
-POS and NEG end
-uneven distribution of charge = share e- unequally
nonpolar molecule
-symmetrical
-pos-pos / neg-neg
-even distribution of charge = share e- equally
TRUE/FALSE- you can have a nonpolar molecule with a polar bond
TRUE (ex. C-Cl)
non-symmetrical molecules (polar)
bent
trigonal pyramidal
see-saw
t-shaped
square pyramidal
symmetrical molecules (nonpolar)
tetrahedral
linear
trigonal planar
trigonal bipyramidal
octahedral
square planar (exception)
if atom has unidentical atoms…can symmetry be disrupted?
yes
spdf stuff
s = 1
p=3
d=5
f=7
must add up to TEP
H-bond
H atom is attracted to F,O,N (high EN)
strongest IMF
responsible for high freezing/boiling point
intermolecular forces
attraction between two or more molecules
Dipole-dipole bond
attraction between oppositely charged regions on POLAR molecules
e- —> to higher EN
intermediate strength
LDFs (London Dispersion Forces)
all molecs have LDFs
-weakest IMF
relationship between molar mass and boiling point
higher molar mass = more LDFS = stronger IMFs = harder to boil = BP up
electrostatic force
attraction between oppositely charged ions
bond length
short = strong (triple bond)
long = weak (single bond)
bond length depends on number of bonds
why do atoms bond?
to become stable
covalent bonds are held together by the attraction between _______and ________
protons in nucleus of one atom+ electrons of other atom - electrostatic force
true/false- LDFs are permanent
false- they are temporary and weak
Do nonpolar/polar molecules have stronger IMFS? Why?
polar- they have dipole-dipole bonds
is water polar/nonpolar?
Polar!!
