Dr B.
Lab: Physical and Chemical Properties and Changes
Physical Chemical Properties and Changes
INTRODUCTION
Physical and chemical changes are pervasive in our daily lives. Physical and chemical properties
are constantly measured to distinguish different matters. The ability to distinguish one from the
other is of great importance. This lab provides opportunities in exploring the detailed and
sometimes subtle differences between the physical and chemical changes, physical and chemical
properties.
PRE-LAB ASSIGMENTS:
1. Draw the experimental setup for using evaporation dish in the lab notebook. Show
details, such as name of each piece of lab equipment.
Sketch:
PURPOSES:
 Understand differences between physical and chemical changes.
 Understand differences between physical and chemical properties.
 Reinforcing good laboratory practices, focusing on observations and note taking.
MATERIALS:
electronic balance
1 test tube
1 spatula
disposable pipets
2 evaporation dishes
1 crucible
tong
2 glass rod
Epsom salt
paper
matches
baking soda
vinegar
magnesium strip
SAFETY:
Wear goggles and apron.
Be alert for potential hazards.
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mortar and pestle
paper
watch glass
150-mL beakers
10-mL graduated cylinder
Dr B.
Lab: Physical and Chemical Properties and Changes
PROCEDURE:
I: Paper
1. Measure the length and width of the paper sample. Record in the data table. Note:
measurements should have proper significant figures according to the instrument(s) used.
2. Mass the paper on electronic balance. Record in the data table.
3. Describe the paper sample in detail. Record in the data table.
4. Tear the paper into two pieces. Observe and record in the data table.
5. Mass all the pieces of torn paper on electronic balance. Record in the data table.
6. Light a piece of paper using a match and put into a 150-mL beaker. Wait 5 seconds. Cover
the beaker with the watch glass. Observe and record in the data table.
II. Epsom Salt
1. Take a large Epsom salt crystal from the instructor.
2. Put a piece of weighing paper on the electronic balance. Zero the balance. Mass the crystal
on the weighing paper and record the data.
3. Observe the crystal and record in the data table.
4. Using the mortar and pestle to smash the large Epsom salt crystals into smaller pieces.
5. Observe and record in the data table.
III. Baking Soda and Vinegar
1. Use the spatula to transfer small amount of baking soda to the bottom of a 35-mL test tube.
2. Transfer approximate 3 mL of vinegar into another test tube using a 10-mL graduated
cylinder. Record the exact volume in the data table. Note: measurements should have proper
significant figures according to the instrument(s) used.
3. Put both test tubes into a 150 mL beaker. Mass on the electronic balance. Record in the data
table.
4. Pour the vinegar into the test tube containing baking soda and observe. Let the mixture sit
for 2-3 minutes. Record in the data table.
5. Mass the whole setup (beaker and two test tubes). Record the data.
DATA:
Data Tables
I.
Paper
a.
b.
c.
d.
e.
II.
Length (cm) _______
width (cm) __________
Mass
_______
Observations ______________________________________________
Total mass of torn __________
Observations during/after fire ________________________________________
Epson Salt
- CIRCLE ONE OF EACH PAIR IN PARENTHESIS
a. Mass of crystal __________ (Qualitative/ Quantitative) (Physical/Chemical)
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Dr B.
Lab: Physical and Chemical Properties and Changes
b. Observation of crystal ______________________________________________
(Qualitative/ Quantitative) (Physical/Chemical)
c. Observation after crushed ___________________________________________
(Qualitative/ Quantitative) (Physical/Chemical)
III.
Baking Soda and Vinegar
a. Volume of vinegar __________ (Qualitative/ Quantitative) (Physical/Chemical)
b. Mass of test tube ___________ (Qualitative/ Quantitative) (Physical/Chemical)
c. Observation of combination ___________________________________________
(Qualitative/ Quantitative) (Physical/Chemical)
d. Mass of set up ____________ (Qualitative/ Quantitative) (Physical/Chemical)
DATA ANALYSIS:
For each recorded observation, determine whether it is qualitative or quantitative; and whether
it is describing a property or change. Further identify each observation to be either chemical
or physical change/property.
II. Epsom Salt
1. Calculate mass of Epsom salt prior to the crushing. Record in Data Analysis section.
2. Calculate mass of Epsom salt after the crushing. Record in Data Analysis section.
3. Calculate the difference between the mass of Epsom salt before and after crushing. Is it a
chemical or physical change?
_________________________________________________________________________
III. Baking Soda and Vinegar
1. Calculate difference between the mass prior and after the mixing.
__________________________________________________________________________
POST-LAB QUESTIONS: (complete sentences)
1. Which processes are physical changes?
___________________________________________________________________________
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Dr B.
Lab: Physical and Chemical Properties and Changes
2. Which processes are chemical changes?
___________________________________________________________________________
3. What are the key differences between properties and changes?
___________________________________________________________________________
4. What are the key differences between physical and chemical properties?
__________________________________________________________________________
5. What are the major signs for the onset of chemical change (reaction)?
__________________________________________________________________________
6. What are the key differences between physical and chemical changes?
__________________________________________________________________________
7. How would one be able to distinguish between intensive and extensive physical properties?
_________________________________________________________________________
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