1.  Width of smile
2.  Length of index finger
3.  Distance of one step
4.  Length of Shoe
5.  Width of wrist
6.  Length of tape A
7.  Length of tape B
8.  Length of tape C
9.  Length of tape D
10.  Door width and height	W = H  =	W = H  =	W = H  =	W = H  =
11.  Room width and length	W =  L   =	W =  L   =	W =  L   =	W =  L   =
12.  Length and width of  floor tile	L  =  W =	L  =  W =	L  =  W =	L  =  W =
13.  Length of chalkboard
14.  Length of object A
15.  Length of object B
16.  Length of object C
17.  Length and width of object E	L = W =	L = W =	L = W =	L = W =
18.  Your height

 

Name_________________________________

Period ____________ Date _______________

Part 2 of Metric Lab

           Density is referred to as the mass per unit volume of a substance. In other words, density is how tightly matter is packed in an object.  Let’s say we compare two objects of equal size.  Object one is wood and Object two is lead.  Both the objects have the same volume.  Both objects are a cubic centimeter. It just so happens that the matter (particles) that make up the wood are farther apart than the particles of matter that make up the lead.  The further apart the particles, the less dense the substance. If you have two trash cans of equal volume and you place the same amount of garbage in both cans, you could say the density of trash can A and B are the same.  What if you climb in trash can B and jump up and down on top of the trash compressing the trash or matter into the bottom of the can.  You can climb out, put more trash in the can and repeat this task until you cannot put anymore trash in can B. Which trashcan would have the greatest density?  Well...........that’s density!           

Let’s determine the density of the objects placed before you.  Remember we are trying to determine how dense or tightly packed the matter is in the objects.  We will use math to help us.  The formula we will us is:

Density = Mass         or         Mass divided by Volume = Density

                Volume
Do you remember what tool scientists use to determine the mass of an object?   Should we use the type of scale that measures body weight or should we use a triple beam balance? If you wanted to figure out the volume of an object or the amount of space an object occupies what tool could you use?

Write the name of the tool you would use to measure mass   _______________________ .

Write the name of the tool you would use to measure volume______________________ .

Since the mass of an object is expressed in grams and the volume of an object is determined in millimeters we are going to express density as grams per cubic centimeter (g/cm3).  Don’t forget that one millimeter is equal to one cubic centimeter.  To compare the density of different objects we must use the same units of measurement.  When we use math to solve for density we are comparing the density of the objects equally.  It would be like cutting each object into a square centimeter and comparing its density.  By following through with proper measurements and doing the math we can compare the density of objects accurately. 

In other words, the substances are cut into a square measuring 1cm by 1cm by 1cm.  Yes they would have the same volume.  Let me give you a practice problem.

If 96.5 grams (g) of gold has a volume of 5 cubic centimeters (cc), what is the density of gold?  Plug these numbers into the formula.

Your Answer: _______________________ (don’t forget to use the correct units, see above)

How did they get these figures?  They first took the gold and determined the mass (grams) by using the triple beam balance.  Secondly they placed the gold carefully into the graduated cylinder and determined its volume.

You should get an answer of 19.3.  Not just 19.3 but 19.3 g/cm3. What does this mean?  Well in each 1cm by 1cm by 1cm square of gold there is 19.3g of matter.  Would this number be higher or lower if we were calculating the density of styrofoam? _____________

You have five objects in front of you.  Determine the density of each object.  Please refer to the information above if you have any questions.  You can also ask me for help if you would like. A calculator will help you solve these problems.  Be sure to write the correct unit after each number.  For example: mass might be 19.3 g, not just 19.3; volume 5 ml, not just 5.

Object # 1               _______________      Object # 6               _______________

Mass of object             _______________      Mass of object             _______________

Volume of object          _______________      Volume of object          _______________

Density of object          _______________      Density of object          _______________

Object # 2               _______________     Object # 7               _______________

Mass of object             _______________      Mass of object             _______________

Volume of object          _______________      Volume of object          _______________

Density of object          _______________      Density of object          _______________

Object # 3               _______________      Object # 8               _______________

Mass of object             ______________        Mass of object             ______________

Volume of object          _______________      Volume of object          _______________

Density of object          _______________      Density of object          _______________

Object # 4               _______________      Object # 9           _______________   

Mass of object             ______________        Mass of object             ______________

Volume of object          _______________      Volume of object          _______________

Density of object          _______________      Density of object          _______________

Object # 5               _______________      Object # 10            _______________

Mass of object             ______________        Mass of object             ______________

Volume of object          _______________      Volume of object          _______________

Density of object          _______________      Density of object          _______________

Choose three of the density blocks and determine its mass, volume and density.  Please indicate the identity of the substance in the space provided.  For example maybe you have chosen aluminum for block #1.  If so, write aluminum in the space to the right of block number # 1.

Block               _______________________

Mass                _______________________             

Volume            _______________________                                                             

Density             _______________________

Block               _______________________

Mass                _______________________             

Volume            _______________________                                                             

Density             _______________________

Block               _______________________

Mass                _______________________             

Volume            _______________________                                                             

Density             _______________________

As a class we have collected the height of each 7^th grade student in Mr. Glassford’s 7^th grade science classes.  In science, raw data or numbers don’t mean as much unless they are compared or graphed.  When we graph our data we can see patterns to help us make conclusions.  Take the numbers given in class (height in centimeters) and create a graph comparing boys and girls, tallest period etc.  You need only one graph.  Place your graph in the space provided below.