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Formula Calculations

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formula mass
mass for any formula
molecular mass
mass for molecule
1 amu
1.6605*10^-24 g
avogadro's number (a mole)
6.022*10^23
molar mass
mass for one mole of the formula
moles to mass
use this conversion for this process:

molar mass/1 mole
mass to moles
use this conversion for this process:

1 mole/molar mass
molecules to moles
use this conversion for this process:

1 mole/6.022*10^23
molecules to mass
use these conversions for this process:

1 mole/6.022*10^23 molecules....then molar mass/1 mole
mass to molecules
use these conversions for this process:

molar mass/1 mole.....then 1 mole/6.022*10^23 molecules
mass of compound to mass of element in compound
use these conversions for this long process:

1 mole/ molar mass...ratios of moles...molar mass/1 mole
percent composition
mass for 1 mole of element*the total number of times it appears in a formula

all divided by

the mass of the entire compound

calculate

then times it by 100%
molecular formula
formula for a complete unit; able to be drawn
empirical formula
smallest whole number ration in formula
how to calculate the moles of each element
element mass % → consider it to be part of 100 g (so just take of the percentage off and replace it with a g for grams) → multiply by molar mass
how to get an empirical formula
get a whole number ratio by dividing by the element with the smallest amount of moles; then multiply to get a whole number ratio