AP CHEM AP TEST REVIEW Flashcards
(46 cards)
Covalent bonds.
Sharing electrons. Have IMFS
The larger the dipole movement the ______ polar the molecule will be
More
Dipole dipole forces
Occur between polar molecules. Weak. Melt and boil at low temperatures. Usually gases or liquids at room temperature.
Hydrogen bonds
Hydrogen bonds with F N or O. strong. Higher melting and boiling points
London dispersion forces
Occur between all molecules. Very weak. Melt and boil at extremely low temperatures. More electrons means higher melting and boiling points though.
Temperature and vapor pressure are _____ proportional
Directly
What are the exception elements to the octet rule?
H and He is stable with 2 electrons
Boron is stable with 6
When can a central atom of a Lewis dot structure have more than 8 electrons ?
When it has d subshells (transition metals)
Molecular geometry
Linear)linear 180
Trigonal planar)trigonal planar-bent 120
Tetrahedral)tetrahedral-trigonal pyramidal-bent 109.5
Trigonal bipyramidal)trigonal bipyramidal-seesaw-tshaped-linear axial to Equatorial is 90 and Equatorial to Equatorial is 120
Octahedral)octahedral-square pyramidal-square planar 90
*subtract 2.5 for each extra pair of electrons except for octahedral structures
Ionic bonds
Occur between metals and nonmetals. Higher melting and boiling points than covalent bonds.
How do you do percent composition
Multiply subscripts my the elements molar mass
Then add all the products together and divide each individual molar mass by that total and multiply, by 100
How to do empirical formula
Convert to moles
Divide my lowest moles and those are the subscripts
How to find molecular formula
Find empirical formula
Find the total molar mass of the empirical formula
Divide given by total molar mass and multiply all subscripts by the value
What does quantized mean?
Electrons can exist only at specific energy levels
Aufbau principle
Electrons are place in order of increasing energy
Pauli exclusion principle
Two electrons in the same orbital have opposite spins
Hund’s rule
Electrons added will always occupy empty orbitals if available
What did mendeleev and Meyer do?
Proposed models for the period table and their trends
What did dalton say?
Always the same ratio of elements and atoms cannot be created or destroyed in a reaction
Thomson’s experiment
Plum pudding model he said that electrons were sprinkled about the atom like a chocolate chip cookie
Millikan’s experiment
Found the charge of an electron by examining the behavior of charged oil drops
Rutherford’s experiment
Gold foil experiment found that positively charged protons were mainly in the center of an atom and that an atom is mostly empty space
Heisenberg uncertainty principle
It is impossible to know both the position and momentum of an electron at a particular instant
That one Radom density and molar mass equation
D=P(MM)/RT
