EXAMINING CHANGES
NAME_______
DATE________
In this activity, you will identify a physical and chemical change.
Materials: safety glasses
hand lens
aluminum foil
copper chloride
rubber stopper
square of paper
test tube rack
PART A: Copper chloride and water
1. Put on your safety glasses. Obtain a small amount of copper chloride on a piece of paper.
Examine using the hand lens.
State
Color
Clarity
Crystal form
2. Examine a test tube of water.
State
Color
Clarity
Viscosity
Odor
3. Pour the copper chloride into the water. Put on a rubber stopper and shake. Examine the
results.
State
Color
Clarity
Odor
4. Keep the copper chloride solution for PART B!!!
Analysis:
1. Did you expect the final color of the solution? Explain____________________________
_______________________________________________________________________
2. Did you make a new substance? How do you know?_____________________________
_______________________________________________________________________
3. At the particle level, describe what has occurred: _______________________________
_______________________________________________________________________
________________________________________________________________________
PART B: Copper chloride and aluminum
1. Examine the aluminum foil.
State
Color
Malleability
Lustre
Texture
Clarity
2. Put the aluminum foil into the test tube of copper chloride solution. Examine and describe
what you see.
_______________________________________________________________________
______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
Analysis:
1. Did you expect the final color of the liquid? Explain__________________________
____________________________________________________________________
2. Did you make a new substance? How do you know?__________________________
_____________________________________________________________________
3. At the particle level, describe what has occurred: _______________________________
_______________________________________________________________________
_______________________________________________________________________
4. Label each of the following as physical (P) or chemical (C) changes:
Disappearance of an air freshener stick
_______
Baking of a cake
_______
Formation of ice cubes
_______
Burning leaves
_______
Exploding dynamite
_______
Formation of acid rain
_______
Magnetizing an iron nail
_______
Dissolving sugar in water
_______
TEACHER NOTES:
This lab is extremely easy to do! Before we start, we usually discuss the differences between
physical and chemical changes but do not include examples (these are added after the
activity to our notes). The physical properties of matter and the particle theory are also
previously covered. The lab is self-directed with the teacher as a facilitator. Usually the
teacher discusses what the students are observing with each group. Make sure you have
them feel the test tube and note the gas bubbles.
The activity works best with small groups of 2 – 3. It takes about an hour including clean up.
Set the materials up before the activity and have the students bring all their materials to their
desk before starting.
You can use a hand lens or a magnifying glass or anything to help view the crystals of the
copper (II) chloride.
The amount of copper (II) chloride is about ½ teaspoon (sorry for the non-scientific terms).
Enough that when the water is added the solution is blue colored. You may need to
experiment.
The aluminum foil is in a strip about 1 cm x 3 cm. Ensure students do not crumble up the
strip – it should fit lengthwise into the test tube.