`States of MatterBarbara Pawela                             Retired                           Objectives: Grades 3-6The students will be able to:   A.  Define matter.   B.  Identify the states of matter.   C.  Tell about the properties of each state of matter.   D.  Demonstrate an understanding of the difference between a physical and       a chemical change.Materials needed:    a variety of solids        Ziploc plastic bags       hot plate    a variety of liquids       clear plastic glasses     crucible    spray perfume              2 Erlenmeyer flasks       ice    2 Tbs. powdered sulfur     round balloons            clear container    2 Tbs. iron filings        food coloring             4 cans    baking soda                acetate fabric            2 beakers or jars    vinegar                    50ml acetone                  1 tsp. salt                watch glassStrategies:Activity I:   1.  Display different solids and liquids.   2.  Put a variety of small solid objects into Ziploc bags, and have a member       of each group pick-up the bags for each student in the group   3.  Discuss the definition of "matter".   4.  Ask the students to take out, look at, and touch the objects.  Ask if        they can see the objects?  Introduce the word "visible".   5.  Together discuss the other properties..  Tell the students to try to        put their pens through the desk.  Ask if they could do so easily?  Tell        them to do the same thing with some of the other objects.  Together        discuss that one cannot go through solids easily.  External force has       to be applied.   6.  Ask the students if the objects keep their shape easily?  Discuss and        conclude that they do if no force is applied to them.Activity II:   1.  Take ice cubes between your hands.  Hold your hands up and ask what is       happening.   2.  Together discuss the change of phase from a solid to a liquid.   3.  Pass out clear plastic glasses half-filled with water.  Point out the        other liquids on the table.  Ask what other liquids they know?   4.  Tell the students to try to put their pens in the water.  Discuss and       conclude that objects can go through a liquid easily.   5.  Have the students pour the water out of the glass into the Ziploc bag.       Discuss what happened and come to the conclusion that a liquid has a        definite volume, but not a definite shape.  Instead it takes the shape       of its container.   6.  Put about a liter of water in a clear container.  Squirt 4 to 6 drops       blue or green food coloring into the water.  Observe what happens.         Discuss "fluidity".Activity III:   1.  Ask the students what is in front of their nose?  Tell them to take       an index card or piece of paper and fan themselves.  Discuss and        conclude that the breeze is made by moving air.  Have the students       blow up their balloons and then let the balloons deflate.  Ask if they       could see the air or the substance that was blown into the balloon.       Introduce the terms "gas" and "invisible".   2.  Spray some perfume.  Let it disperse throughout the room.   3.  While the perfume is dispersing, take the Erlenmeyer flask, in which       the water should be boiling for at least a minute, off the heating unit       and immediately place the balloon opening over the flask's mouth.   4.  Let the water balloon cool (the balloon will be sucked inside out into       the flask).  If the flask is carefully heated again the balloon will       expand and come out of the flask.  Discuss what was happening.   5.  Discuss the aroma in the room.  Ask how the aroma was dispersed.Activity IV:   1.  Give each group a can containing ice.  Let water condense on the outside       of the cans and then ask if the cans are leaking.  Discuss from where       did the water come.  Together continue discussing the change of phase       from a gas to a liquid.   2.  State that matter can undergo other types of changes besides the change       of phase.  Have the students tear their paper.  Have them mold the clay       into different shapes.  Discuss the fact that, though a change has        occurred, the basic material is the same substance.   3.  Cut an apple into pieces.  Again point out that cutting an apple was a       physical change and the substance of the apple was the same.  Place some       of the apple pieces into the crucible.  Add a little water and place        the crucible on the hot plate to cook.  Leave some of the raw apple        pieces exposed to the air.   4.  Put 1/2 tsp. salt into 50ml water.  Stir until the salt dissolves.       Take about 10 ml of solution and put on a watch glass.  Place on a       hot plate.   5.  Take 1 tsp. powdered sulfur and mix it with about 1/2 tsp. iron       filings.  Mix the sulfur and iron.  Place a magnet over the mixture.       The iron filings will be pulled out by a magnet.  Discuss and conclude       that the mixing had been a physical change.   6.  Check on the apples and on the evaporating salt solution.  The apple        should have cooked some.  Discuss how the apple has changed.  Conclude       that the apple is different from the raw apple and will not change        back.  Look at the watch glass after the water has evaporated.  Look at        the residue and discuss what happened.   7.  Burn part of the paper.  Discuss and conclude that the paper has        undergone a chemical change.  The actual substance has changed to        something else, and burned paper cannot be returned to the original       substance.   8.  Heat the 1 tsp. powdered sulfur mixed with 1/2 tsp. iron filings.  Observe        what happens.  A gas is given off.  A new substance has formed.  Allow it       to cool.  Test for magnetic attraction.  Discuss and conclude that a       chemical change occurred.   9.  Cut a small piece of acetate fabric.  Ask what kind of change this was.       Put the piece of fabric into 50 ml acetone in a  beaker or similar jar.       The fabric will dissolve.  Together discuss that this is a chemical        change.  Repeat the process dissolving styrofoam in the acetone.  10.  Give each group a candle.  Light the candles.  Observe and discuss what       is happening.  Conclude that the burning candle is an example of both a       physical and chemical change.  Some of the wax melts into a liquid and        later cools down and solidifies back into its original substance.  Some       of the melted wax was heated enough to change into a gas which burned.Performance Assessment:    Part of the assessment are the students' responses during the discussions.    The final part of the assessment is as follows:         You have been hired by a sea-bordering, desert country to provide        drinking water from sea water.  You are to purchase materials and design        a process to provide fresh water.  Explain what equipment and materials       you would use.  Draw a diagram and explain your procedure.`