Download LAB – Observing Changes in Matter

Science 9 – Chemistry Unit
Name: ______________________________
Date: __________________ Block: ______
LAB – Observing Changes in Matter
Physical and Chemical Changes
Excellent
A
Data Collection
Discussion Questions
Conclusion
B
Proficient
C+
Adequate
C
C-
Not Yet Meeting
I
All required elements are
included in the
assignment.
Most required elements
are included in the
assignment.
Some required elements
are incomplete OR
inaccurate.
Several required
elements were missing
OR inaccurate.
- Properties of reactants
- Description of change
- Determine if reaction
was a chemical or
physical reaction
- Reason why you chose
physical or chemical
Students can accurately
answer all questions.
- Properties of reactants
- Description of change
- Determine if reaction
was a chemical or
physical reaction
- Reason why you chose
physical or chemical
Students can accurately
answer most questions.
Students have accurately
completed the entire
conclusion.
Students have accurately
completed much of the
conclusion.
- Properties of reactants
- Description of change
- Determine if reaction
was a chemical or
physical reaction
- Reason why you chose
physical or chemical
Students can answer
some of the questions
accurately.
Students have accurately
completed some of the
conclusion.
- Properties of reactants
- Description of change
- Determine if reaction
was a chemical or
physical reaction
- Reason why you chose
physical or chemical
Students have not
accurately answered the
questions.
Student has not
completed the
conclusion.
Purpose: to investigate the differences between physical and chemical reactions
Background:
In this lab, you will carry out 6 different experiments and record the information into the data
table found in the Data/Observations section. Record the properties of the reactants before doing
the reaction. Remember, safety first! There is acid being used.
Safety goggles and lab aprons are a must!
Reaction 1
Materials:
Test Tube
Calcium Chloride
Water
Graduated cylinder
Procedure:
1. Put 1 small scoop of calcium chloride in the bottom of the test tube.
2. Hold the test tube at the bottom, and fill the test tube with 5 mL of water. Take note of what
you feel at the bottom of the test tube.
Clean-Up
1. Pour the calcium chloride solution down the sink, using lots of water to rinse it down.
2. Rinse out the test tube, using a cleaning brush to clean it out.
3. Put the test tube back into the test tube rack.
Reaction 2
Materials:
Steel wool
Magnesium ribbon
Dilute hydrochloric acid (0.5-1.0 M HCl)
Test tube
50 mL beaker
Please find the procedure on the next page of this lab.
Procedure:
1. With the steel wool, polish a piece of magnesium ribbon. Examine it.
2. Pour dilute hydrochloric acid into a test tube to a depth of about 4 cm. Remember to pour the
acid from the stock into your own beaker (20 mL or enough to cover the magnesium strip).
3. Add the magnesium ribbon to the test tube.
Clean-Up
1. Pour the solution of hydrochloric acid down the sink, using lots of water to rinse it down. Make
sure that you don’t pour the magnesium strip down the sink.
2. Throw the magnesium strip that is left into the garbage & rinse hands off.
Reaction 3
Materials:
Sodium carbonate solution
Calcium chloride solution
Two test tubes
Two 50 mL beakers
Procedure:
1. Fill one test tube half way with sodium carbonate
2. Pour 10 mL of calcium chloride solution into a second 50 mL beaker.
3. Carefully pour 10 mL of calcium chloride to the sodium carbonate test tube.
Clean-Up
1. Pour the sodium carbonate + calcium chloride solution down the sink, using lots of water to
rinse it down.
2. Rinse out the beaker, using a cleaning brush to clean it out.
Reaction 4
Materials:
Test tube
Milk
Acetic acid (Vinegar)
Procedure:
1. Fill one test tube up half full with milk.
2. Add 10 mL of vinegar to the test tube with the milk in it.
Clean-Up
1. Pour the milk + vinegar solution down the sink, using lots of water to rinse it down.
2. Rinse out the beaker, using a cleaning brush to clean it out.
Reaction 5
Materials:
Beaker
Scoopula
Sodium bicarbonate
Water
Procedure:
1. Place one scoop of sodium bicarbonate into the beaker.
2. Add 100 ml water to the beaker.
3. Stir for 1 minute.
Clean-Up
1. Pour the sodium bicarbonate + water down the sink, using lots of water to rinse it down.
2. Rinse out the beaker, using a cleaning brush to clean it out.
2
Reaction 6
Materials:
Sodium bicarbonate
Acetic acid (vinegar)
2 Test tubes
Two 50 ml beakers
Procedure:
1. Place one scoop of sodium bicarbonate into a test tube.
2. Fill the second test tube about ¼ full with vinegar.
3. Pour the vinegar into the test tube containing sodium bicarbonate.
Clean-Up
1. Pour the sodium bicarbonate + acetic acid solution down the sink, using lots of water to rinse it
down.
2. Rinse out the beaker, using a cleaning brush to clean it out.
Data/Observations:
Reaction
Properties of Starting
Materials (Reactants)
Detailed Description
Calcium Chloride -
Description of Change
(Observations of Products)
Physical
or
Chemical
Indication for
Chemical Change
1
Calcium chloride + water
Water –
Magnesium 2
Magnesium +
Hydrochloric acid (HCl)
HCl Sodium carbonate -
3
Sodium carbonate +
calcium chloride
calcium chloride –
Milk 4
Milk + acetic acid
(vinegar)
Acetic acid –
Sodium bicarbonate 5
Sodium bicarbonate +
water
Water Sodium bicarbonate -
6
Sodium bicarbonate +
acetic acid (vinegar)
Acetic acid –
3
Discussion Questions:
1. Define physical change.
2. Define chemical change.
3. Name five indicators that suggest a chemical change has occurred.
a. ___________________________________________________________
b. ___________________________________________________________
c. ___________________________________________________________
d. ___________________________________________________________
e. ___________________________________________________________
4. a. How can you tell if a temperature change has occurred if you do not have a thermometer?
______________
b. In which reaction(s) was there a temperature change?
____________________
5. In reaction #3, the products of this chemical reaction are calcium carbonate and sodium chloride.
Write a word equation for this reaction. (hint: where would you find the reactants?)
____ ____  _________________________________________
Conclusion:
In this experiment, the differences between
_________________ __ and
_______
changes were observed. A physical change has occurred when
. A chemical change has occurred when
. A good example of a physical change is when
and a good example of a chemical change is when
______________
______________
.
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