AAMC Practice Flashcards
pH equation (given acid concentration)
ph = -log[H+]
solving log equations
determine molecular geometry: basic steps
determine the steric number
determine the geometry based on the number of bonds and lone pairs
steric number
the number of “electron dense areas” around a central atom
lone pairs or bonds (whether single, double, or triple)
molecular geometry: steric # 2, no lone pairs
linear
180° bond angle
molecular geometry: steric # 3, no lone pairs
trigonal planar
120° bond angle
molecular geometry: steric # 3, 1 lone pair
bent
<180° bond angle
molecular geometry: steric # 4, no lone pairs
tetrahedral
109.5° bond angle
molecular geometry: steric # 4, 1 lone pair
trigonal pyramidal
109.5° bond angle
molecular geometry: steric # 4, 2 lone pairs
bent
<109.5° bond angle
Boiling point
temperature at which the vapour pressure of the liquid equals the surface pressure
Red litmus paper
basic substance → turns blue
acidic or neutral substance → stays red
which ions are often responsible for colour in solution
complex ions containing transition metals (d block elements) are usually coloured, whereas the similar ions from non-transition metals aren’t
electrons in the lower energy d orbitals absorb visible light to move to the higher energy d orbitals
“carboxyl group”
the functional group COOH
carboxylic acid
a compound with a carboxyl group attached
hydrolysis
(to be hydrolyzed)
add water to break bonds
dehydration synthesis
bonds are formed as water is released
Triglyceride
ester
how are esters formed
from a carboxylic and and alcohol
an ester bond is formed and a water molecule is released
High retention factor (Rf) value = ____________
further distance travelled
retention factor (Rf) formula
silica gel is ________ (polar/nonpolar)
polar
(other polar substances ‘stick’ to it)
mmol to mol conversion
1 mole = 1000 mol
Equilibrium constant (Keq) equation
equation for amount of heat gained or lost from a system
q = mc∆t
isopropyl group
tert butyl group
atomic radii trends on periodic table
bottom left = largest
top right = smallest
of protons
determined by atomic number
of electrons
= atomic number
(same as # of protons)
of neutrons
= atomic mass - # of protons
(atomic mass = protons + neutrons)
ionic bonds usually occur between… (2)
metals and nonmetals
usually between elements on the far left and far right of the periodic table
wedge and dash to chair conformation
wedge = _______ (up/down)
dash = _______ (up/down)
wedge = UP
dash = DOWN
Metals are on the _____ (left/right) of the periodic table
Nonmetals are on the _____ (left/right) of the periodic table
Metals are on the LEFT of the periodic table
Nonmetals are on the RIGHT of the periodic table
electronegativity differences and bond type
Electronegativity trends in periodic table
Graphite is composed of which element?
carbon
negative delta S meaning
entropy decreases
positive delta S meaning
entropy increases
Gibb’s Free energy equation
2 characteristics of ideal gases
molecules have no intermolecular forces and occupy no volume
