Density Problems!  Whoo Hoo!

Basic Formula: D = m / v
D = density m = mass v = volume
 
Units: Density will always be a mass unit over a volume unit.  (g/ml) (g/cm3)
Mass units:  g (grams) kg (kilograms)  Volume Units: ml, L, cm3

 

These problems are not really very hard to solve as long as you match the given numbers (usually using their units) with the formula above.  You can also use the triangle method.  The triangle is an easy way to figure out how to manipulate the formula.  In order to use it, look at the triangle.  Put your finger over the variable or letter you need to solve for.  For example, if you are looking for the density, you will cover up the letter D.  Now you do the mathematical function it shows.  If the letters are beside each other, you multiply.  If one is on top of the other, you divide.  If you would like to check out some sample problems, click on this link:  <density sample problems>
The triangle:

You can see that if you were trying to solve for Density.  Then the M (g,kg) would be over the V (mL, L), so you would divide the mass by the volume.  Similarly, if you wanted to solve for Volume (mL, L) , then the mass (g, kg) would be divided by the density since the mass is on the top. If you wanted to solve for Mass (g, Kg) , then the Density (g/mL) would be located beside the Volume, so you would multiply them together. 

(Units are included in italics in the parenthesis)

 

Last Updated: April 8, 2005.  All Rights Reserved.  If you have any questions or comments, please contact the IPCWebmaster. test