What is Mass? Mass is the amount of matter composed

in an object. Don’t get this confused with weight,

because weight is simply a gravitational pull on matter.

What is Density? Density is the ratio of the mass of a

substance to the volume of the substance, best demonstrated through the provided formula, Density=Mass/Volume.

This is often expressed as grams per cubic centimeter for solids and liquids.

For gases, however, it’s expressed as grams per liter.

Here’s a visual to help better show how density increases as mass increases.

What just happened?

As you can see, as air continues to flow into the inflatable ball, mass increases, therefore since the ball’s circumference is concealed, density also increases.

Thus expanding the ball to the point where it will eventually pop, or the hose inputting the air will basically remove itself.

Observe:

WHAT HAPPENED…? As you observed from the visual, the

hose removed itself from the ball, and the ball randomly flew around, (while losing mass, thus losing density), until it shriveled up to almost nothing.

Now that you know the relationship between mass and density, you can now use the formula:

Sample Problem A sample of aluminum metal has a mass of 8.4g.

The volume of the sample is 3.1cm^3. Calculate the density of aluminum.

First, let’s use the formula, Density=Mass/Volume. Second, let’s plug in our givens: Density=8.4g/3.1cm^3 Third, just divide through: Density= 2.7g/cm^3

There, simple as that. Now wasn’t that easy?.... But, GASP, what if only the density and mass are

given and we have to find the volume?!

Sample Problem 2

No…not that…. What we’d do is we’d rearrange the equation. Let’s say that our givens were: Density=2.7g/cm^3 Mass=8.4g Then we’d set up our equation like so: 2.7=8.4/x (Multiple x by 2.7) 2.7x=8.4 (Divide by 2.7) x=3.1cm^3, which is the volume. Good Job! (Commence dancing)

ConcludingYou can rearrange the equation to solve for

any missing variable, as long as two have already been provided for you, or you have other means for solving for one of the missing variables.

Thanks for watching!Project: #14Group: Chris Fiechter and Olivia LangfordClass: Pd 6/PIB Chemistry/HughesMusic: Viva la Vida Instrumental