Lesson 4 Properties of Matter

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Lesson 4 Properties of Matter Powered By Docstoc
					  Properties of Matter

 Anything in red type or on a red slide, you do not
need to put into your notes. Everything else, you are
          expected to put into your notes.
     Pre-Assessment Questions
   What is matter?
   Can you give an example of matter?
   Are mass and volume the same thing?
   What is density?
Matter – anything that
 takes up space and
 has mass
     Which of these are matter?
   You              Water
   Table            Air
   Dog              Carbon dioxide
   Pop              Light
   Everything in the universe is
    either MATTER or ENERGY.
    Matter has physical properties.
   Physical properties – characteristics that
    can be used to identify and describe
    materials. Any property that can be
    observed or measured is a physical
   Examples include: color, shape,
    brittleness, density, length, width, height,
    mass, and volume.
Science uses the
metric system to
            Measuring Mass
   Mass is the amount of matter (number of
    atoms) in an object.
   Mass does NOT change unless you add or
    subtract matter.
   In this demonstration, how could I change
    the mass of the water?
  We measure mass with a
   balance scale.
Steps in using a triple-beam
1. Carry the scale carefully
   using both hands. (They
   cost about $100 each, so
   please treat them nicely.)
2.   Zero the scale - first move all
     the masses to the zero
     position, see if the line is at
     zero. If not, gently turn the
     knob at the end and allow it
     to balance. Repeat until the
     line is at zero.
3.   Put the object on the pan.
4.   Move the masses until the
     lines are lined up.
5.   Record the total mass.
Practice using the triple beam
       balance scales.
   Get a partner and one scale for both of you
    to use.
   Zero the scale.
   Take turns measure the masses of objects
    such as a pen or pencil, a planner, a ruler, a
    glue stick, or other reasonably small object.
   When you are both confident in using the
    scale, call your teacher over to test you.
 Mass is measured in grams.
 1000 grams = ____ kilogram

 1 gram = ____ milligrams
       Measuring Volume

 Volume   is the amount of space
  an object occupies.
 Solids and liquids have a
  definite volume – that means
  you can’t change it without
  adding or subtracting matter.
 Gases  can compress or expand
  to the size of their container,
  so their volume can change;
  it’s NOT definite.
 Watch the demonstration.
  Which type of matter can be
  squeezed into a smaller space?
    We measure the volume of
     liquids with a graduated
   Graduated cylinders are made
    of glass and will break if
    dropped. Please be careful
    with them!!
Steps in using a graduated
1.Put the liquid in it.

2.Place it on a flat surface.
3.   Get down to read it at eye
4.   Read it at the bottom of
     the smile (meniscus).
    Practice using the graduated
   With a partner, get a graduated cylinder.
   Try to get exactly 50 ml of water in it.
   Have your partner check you.
   Repeat for different amounts until both of
    you are confident in using it.
   Call your teacher over to quiz you.
 Volume   is measured in liters.
 1000 liters = ____ kiloliter

 1 liter = ____ milliliters
   We measure volume of a
  regular solid by using math.
 Tofind the volume of a box
 you multiply length times
 width times height.
V = l x w x h
 A box has a length of 10 cm, a
  width of 5 cm and a height of 2
  cm. Find volume.
V = l x w x h

 V = 10 cm x 5 cm x 2 cm

 V = 100 cm3

 cm times cm times cm = cm3
    Time to try finding volume in a
               mini lab!
   Get a partner and find the volume of at
    least 2 of the boxes in lab.
   Write down each measurement and your
    final answer.
          The Box Volume Lab
   Get the lab sheet and follow the
    instructions carefully!

   Link to the lab sheet!
We find volume of an irregular solid
 using the submersion method:

    An example of an irregular solid is a rock.
    To find its volume:
    1.   Put water into a container such as a
         graduated cylinder.
    2.   Note how much water there is.
    3.   Put the object in and the water rises.
    4.   Note how much the water rose and that’s the
          Why does this work?
   Since volume is the amount of space an
    object takes up, when you put an object
    in water it displaces the water. This
    means that the water still takes up the
    same amount of space for itself plus the
    amount of the object, so the water rises
    the amount of the volume of the object.
       Time for you to try in lab.
   With a partner find the volume of one or
    two of the irregular objects.
   Call your teacher over when you are
    confident you know what you are doing.
Okay, now that you understand
mass and volume, let’s put them
   Which weighs more – a pound of feathers
    or a pound of lead?
   Actually, they weigh the same. But which
    takes up more space?
   Density is a measure of how closely
    packed the atoms are in a substance.
   density = mass divided by volume
   d = m/v
                An example:
   An object has a mass of 30 grams and a
    volume of 6 milliliters. What is its density?
   m= 30 g      v= 6 ml
   d=m/v        d= 30g/6ml
   d=5 g/ml
     You try a couple density problems!

1.   mass=100 grams,       Answers:
     volume=20 ml      1.   5 g/ml
2.   mass=7 grams,     2.   .5 g/ml
     volume=14 ml      3.   8 g/ml
3.   mass=40 grams,
     volume=5 ml
           Time for a lab!
           Density Lab 1

Get a partner.
Open a new spreadsheet and write
  down the question.
 Question: How do you think we
  could find out the density of water?
Next do background research, and a
Then we will discuss your ideas about
 how to do this lab.
And then everyone can do the lab after
 we agree on the experimental
               Density Quiz
1.   What is the equation for density?
2.   I have two cube shaped objects that
     have identical volumes. Cube A has a
     mass of 100 grams and cube B has a
     mass of 70 grams. Which cube has a
     higher density?
3.   A box has a mass of 20 grams and a
     volume of 5 cm3. What is its density with
4.   A sample of liquid has a volume of 7 ml
     and a mass of 35 grams. What is its
5.   I have a liquid of unknown density. What
     two pieces of lab equipment would I use
     to find density?
6.   I have a box of unknown density. What
     two pieces of lab equipment would I use
     to find density?
7.   I have an oddly shaped rock of unknown
     density. What two pieces of lab
     equipment would I use to find density?
              Quiz Answers
1.   d=m/v
2.   Cube A
3.   4 g/cm3
4.   5 g/ml
5.   Graduated cylinder and balance scale
6.   Ruler and balance scale
7.   Graduated cylinder and balance scale
     (and maybe a beaker)
           Density Lab 2
 Open a new spreadsheet and type in
  the problem: Rank the five objects in
  order of increasing density.
 For background research give the
  definitions for mass, volume, and
  density and the equation for density
 For your hypothesis pick up and look
  at each of the objects and make your
  best educated guess in ranking them
  from lowest to highest density.
 Next, decide how you will find out if
  your hypothesis is correct and write
  down the steps of your experimental
 Make a data table in the spreadsheet
  for your results. The table should
  have columns for object, mass,
  volume, density, and rank.
 Do the experiment and fill in the
  results in your table.
 For your conclusion list the objects in
  order of increasing density.
 To verify ask another group that used
  the same objects if your results agree
  with yours.