Formula/how To Do Shit For Exam 2 Flashcards
How to determine empirical molecular formula
Change %to g (if necessary) 60%=60g
Change g to moles
Divide bigger number of moles by smaller number
Find whole number
How to determine percent composition
mol of atom in formula x atomic weight
Divide by molecular weight
Multiply times 100
How to find empirical formula from percent mass
Grams (%=g) / atomic mass
^this equates to moles
Find the common multiplier
Multiply all subscripts
How to know if a bond is ionic or molecular/covalent
Ionic-between mental and non mental
Molecular- between two non mental and form covalent bond
the relationship between mass and dispersion forces
the greater the mass, the stronger the dispersion force
the relationship between number of electrons and london dispersion force
london dispersion force increases as number of electrons increases
The larger the cloud of electrons surrounding a nucleus in an atom or the multiple nuclei in a molecule, the more likely those electrons are to be distributed unevenly, or polarized.
the relationship between polarizibility and temp dipoles
the greater the polarizability, the stronger the temporary dipoles and the stronger the intermolecular forces
boiling point and molar mass
the larger the molar mass, the higher the boiling point
constitutional isomer
set of compounds with same moleculat formula but different connections between the atoms in their molecules
(also called structural isomer)
dipole dipole interaction
an attraction between regions of polar molecules that have partial charges of opposite sign
when does hydrogen bonding occur
when F, O or N bonds to hydrogen
The strength of intermolecular forces (and therefore impact on boiling points) is
ionic > hydrogen bonding > dipole dipole > dispersion
