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How can matter be identified based on physical properties?
What are physical properties?
Physical properties are any characteristics of a material, that must be observed without
changing the identity of the material.
Compare the following in DOUBLE BUBBLE:
Cotton Candy and Table Salt
Density – amount of mass in a given volume
• Unique to every substance
• Does not change = physical constant
• Can be used to identify unknown materials
Color Code Your Density Equation
• D = Density (g/mL or g/cm3)• M = Mass (grams or g)• V = Volume (milli-liters or mL)
(centi-meters or cm3)
D = MV
Density Equation
Top of Paper
Density Equation
Practice 1: write question in notes.
• What is the density of sample if its mass is 44.3 g and its
volume is 22.1 cm^3?
Densities of common substances:
• Water 1.0 g/cm3
• Alcohol .789 g/cm3
• Gold 19.3 g/cm3
• Air .00129 g/cm3
Rounding Rules
• 0 to 4 ADD NO MORE
• 5 to 9 ADD ONE TO THE LINE
• So for example:• 0.53 • 0.5
• So for example:• 0.57• 0.6
Round each number to the nearest tenth.1 ) 9.54 2 ) 5.873 ) 5.924 ) 5.245 ) 5.646 ) 7.777 ) 1.888 ) 1.549 ) 2.42
Practice Problems
• Always follow these steps and show all work:
To solve this problem, first I …
Then I …
This answer is …
… because
D = M / V
Write the equation!
Fill in the variables, number and units!
D = 44.3 g / 22.1 cm^3
Calculate and give the answer with unit(s)!
D = 2.0 g/cm^3
Always round to the tenth position for example 1.12 would be 1.1
Answer the following:
• 1. = #7 (no decimal)
• 2. = #2
• 3. = #3 (no decimal)
• 4. = #4
• 5. = #6
OMIT #5 on paper…skip it and go to #6!
Use the @ sign for your decimal.
Density = mass Volume
• A piece of tin has a mass of 16.52 g and a volume of 2.26 cm3. What is the density
of tin?
A man has a 50.0 mL bottle completely filled with 163 g of a slimy green liquid. What is
the density of the liquid?
1930 grams of an unknown metal has a volume of 10 cm3. What is the density of
the metal? What metal is it? (Look in your notes)
The Magic TriangleA piece of metal has a density of 11.3 g/cm3 and a volume of 6.7 cm3. What is the
metal’s mass?
The density of a piece of brass is 8.4 g/cm3. If the mass of the brass is 510 grams, find the volume of the brass.
Density Lab• Find the density of
unknown objects.– D = M / V– Density = Mass / Volume– Get mass and volume of
each object and solve for density.
– Match density to the chart and tell me what you got.
• 2 cubes: (hint – l * w * h)– A = small cube– B = big cube
• 1 odd shaped object (hint – graduated cylinder)
Color Density
Gold 19.30 g/mL
Copper 8.9 g/mL
Brass 8.0 g/mL
Steel 7.6 g/mL
Aluminum 2.7 g/mL
Acrylic 1.16-1.19 g/mL
Nylon 1.13 g/mL
PVC 1.39-1.42 g/mL
Use this chart to answer questions: