1. lecturePLUS Timberlake
9/20/10 Physical Science
Purpose: To be able to define & calculate densities and be able to make the measurements to get density.
Agenda
Get out your warm up sheet
Warm up
Few notes on density
½ class take measurements lab practicum
½ class work on density practice problems
Switch
Finish lab practicum for homework
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2. lecturePLUS Timberlake
9/20/10 warm up
What is mass? What are the metric units of mass?
What is volume? What are the units of volume?
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3. New piece of paper: Density notes
What is density?
How do we calculate density?
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4. lecturePLUS Timberlake
Please write 3-step method at the top of your notes b/c it is required for density problems.
3 steps:
Write equation in words.
Plug in values with units.
Write answer with units and box it!
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5. lecturePLUS Timberlake
Density compares the mass of an object to its volume
Density = mass in g (or g
volume mL cm3)
D =
When do you use g/cm3?
Only when it’s a solid or if the problem gives you those units!
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6. Be able to use it every way!
d=m/v
m= ?
-m=dv
v=?
v= m/d
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7. lecturePLUS Timberlake
Learning Check 1
Osmium is a very dense metal. What is its
density in g/cm3 if g of the metal occupies
a volume of 2.22cm3?
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8. lecturePLUS Timberlake
Volume Displacement
A solid displaces a matching volume of water when the solid is placed in water.
33 mL
25 mL
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9. lecturePLUS Timberlake
Learning Check 2
What is the density (g/mL) of 48 g of a metal if the metal raises the level of water in a graduated cylinder from 25 mL to 33 mL?
33 mL
25 mL
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