1. Separating Mixtures
The components of a mixture can be separated based on the physical properties of:
Magnetism
Density
An instrument that uses this property to separate mixtures when tiny solid particles are dissolved in a liquid is called a centrifuge.
Some techniques used to separate the components of a mixture are:
Filtration
used to separate liquids from solids
Evaporation or distillation
used to separate solutions
Episode 203

2. Density Mass per unit volume Density = mass/volume
Per means “divide”
Density = mass/volume
Common units for density:
g/mL
g/cm3
Episode 203

3. Suppose we have an object with a mass of 5. 0 grams ans a volume of 2
Suppose we have an object with a mass of 5.0 grams ans a volume of 2.0 mL. What would the density of this object?
5.0 grams
2.0 mL
2.5 grams/mL
Episode 203

4. Problem Set One
Given a mass of 12 g and a volume of 3 mL, calculate the density.
What is the mass of 50 mL of water? (Density of water is 1 g/mL)
Given that the density of iron is 7.9 g/cm3, what would be the volume of a 15.8 g piece of iron?
12 grams
= 4 grams/mL
3 mL
m = Dv
1 g/mL x 50 mL
= 50 grams
15.8 grams
v = m/D
= 2.0 cm3
7.9 g/cm3
Episode 203

5. Problem Set Two
Find the density of a block with a length of 4.0 cm, a width of 3.0 cm, a height of 2.0 cm, and a mass of 36 grams.
Find the density of an 8.0 g rock if the water in a graduated cylinder rises from 20.0 mL to 23.5 mL when the rock is placed into the cylinder.
You have a piece of silver with a mass of 31.5 g. Silver has a density of 10.5 g/cm3. What would be the new level of water if this piece of silver is placed into 15 mL of water?
36 grams
= 1.5 grams/cm3
4.0cm x 3.0cm x 2.0 cm
8.0 grams
= 2.3 grams/mL
23.5mL – 20.0mL
31.5 grams
v = m/D
= 3.00 cm3 or mL
10.5 g/cm3
15 mL mL = 18mL
Episode 203