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Density Problems
How to Solve Density Problems:
These questions will include the words mass (or grams) and volume.
Reffy, Table T (p.12)
This is really simple! Just plug the values into the equation.
Mole Calculations number of moles =
A brick of salt has a mass of 433 grams and volume of 200cm . What is its density?
433 = 2.2 g/cm3 measured value – accepted value
200 Percent Error % error = accepted value × 100
The density of all the elements at STP (standard temperature and pressure) are listed on
Reffy, Table S (pp. 10Pe,r1c1e)n.t Composition % composition by mass = mass of part × 100 mass of whole
Table T
Important Formulas and Equations
Density
m d = density d = V m = mass
V = volume
given mass
3 gram-formula mass
The masses of all the elements are listed on the top left of the Periodic Table (
Reffy).
× 1 000 000
Concentration
parts per million = mass of solute mass of solution
molarity = moles of solute liter of solution
PV PV
P = pressure
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