characteristic physical properties some examples of quantitative physical properties include:...
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Characteristic Physical Properties
Some examples of quantitative physical properties include:
• Density • Freezing point• Melting point• Boiling point
These properties can be used to identify a pure substance.
DENSITY
To calculate the density of a substance, we need two pieces of information;1. mass
• measured in mg, g, kg using a scale or balance
2. volume • measured in mL, L using a graduated cylinder
or cm3, m3 using a ruler
Measuring Volume of a Small Irregular Object
Displacement Method
• Fill graduated cylinder partially with water
• Read initial volume• Place in solid• Read final volume
Volume solid = Volume final – Volume initial
Measuring Volume of a Large Irregular Object
Overflow Method
• Fill overflow can until water starts to pour out• Place in solid• Collect the overflow water in a graduated cylinder
Volume solid = Volume overflow
GivenState what the question is giving you.(Don’t forget the symbols and units)
m = 12 gV = 15 mL
RequiredWhat does the question ask you to find?Use appropriate symbols.
D = ?
AnalysisRearranged equation that you will use to answer the question.
D = m / V
SolveSolve the problem. Make sure to include the units.
StatementMake a statement with the answer and units.
the density of the liquid is 0.80 g/mL.
The GRASS Method for Problem Solving
Example 1:A softball has a mass of 360 g and a volume of 270 cm3. Find its density.
Given: Required:
Analysis: Solution:
Statement:
Mass, m = 360 gVolume, V = 270 cm3
Density, D in g/cm3
D = 360 g 270 cm3
D = 1.33 g/cm3
the density of the softball is 1.33 g/ cm3
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Example 2:Calculate the density of a metal sample that is 18.00 cm long, 9.21 cm wide, and 4.45 cm high and that has a mass of 14.25 kg. What is the identity of the metal?
Given:
Required:
Analysis:
l = 18.00 cm m = 14.25 kg w = 9.21 cmh = 4.45 cmV (cm3)D (g/cm3)
V = lwh 𝐷=𝑚𝑉
Solution:
Statement:
D = 14.25 kg 738 cm3
D = 0.0193 kg/cm3
the density of the metal is 19.3 g/cm3
The metal is gold.
Example 2:Calculate the density of a metal sample that is 18.00 cm long, 9.21 cm wide, and 4.45 cm high and that has a mass of 14.25 kg. What is the identity of the metal?
V = l w hV = (18.00 cm)(9.21 cm)(4.45 cm) V = 738 cm3
D = 19.3 g/cm3
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