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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

molar mass/1 mole

mass to moles

use this conversion for this process:

1 mole/molar mass

1 mole/molar mass

molecules to moles

use this conversion for this process:

1 mole/6.022*10^23

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

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

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

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%

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