honors chem Flashcards
How to round for sig figs when multiplying/dividing?
Smallest number of sig figs in original
Sig figs for adding/subtracting?
Smallest number of decimal places in original
List the significant zeroes
Trapped/captive, trailing with decimal
List unsignificant zeroes
Leading, trailing w/o decimal
What is conserved during physical and chemical change?
Mass
Distillation separates mixtures based on what?
Differences based on boiling point
Chromatography separates mixtures based on what?
Differences based on polarity
Explain how paper chromatography works
Component most similar in polarity to mobile phase moves up farthest.
Isotopes
Diff number of neutrons
Ions
Diff number of electrons
What is something called when it has a different number of protons?
Entirely new element w new name
Dalton’s postulates wrong about
Existence of subatomic particles and isotopes
What did the Cathode ray tube discover
negatively charged electron
What did the gold foil exp. dicover?
Dense, positively charged nucleus and mostly empty space in atom
How many electrons can each orbital hold?
2
Aufbau principle
Fill lowest energy level orbital first
What are the rows called?
Periods
What are columns called?
Groups/families
Everything in the same group has ____ bc ____
similar properties bc they have same number of valence electrons
Strength of IMFs and Bulk Solids
lDF < Dipole-dipole < H-bond < ionic < metallic < network covalent
Increase in IMFs corresponds to?
Increased boiling point, melting point, surface area, viscosity
Mole highway pathway
grams A –> moles A –> moles B –> grams B
% composition by mass for a ____ does not change
pure compound
Empirical formula rhyme
% to mass, mass to mole, divide by small, times until whole; get the simplest whole # ratio of the moles in compound
% yield
experimental/theoretical
% error
(experimental - theoretical)/theoretical
Rate affecting factors
temperature, conc./pressure, surface area, catalyst
Rate constant has units based on
overall order of rxn (1-n)
q>k means
too many products, reverse rate increases, shifts left
q<k means
too many reactants, forwards rate increases, shifts right
Use 5% rule when
k<1 and x <5% of starting conc.
Strong acids and bases _____
dissociate completely
Weak acids and bases _____
only dissociate a little
Use ICE Tables for
weak acids and bases
Equivalence point for titration is when
moles of acid = moles of base
Oxidation is
loss of e-
Reduction is
gain of e-
