Density - Mr. Sault's Classroom

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 Density: The amount of
matter that occupies a
certain space.
Densities of Common Elements
and Compounds
Substance
Density
grams per mL or cc
Water
1.00
Aluminum, Al
2.70
Iron, Fe
7.80
Gold, Au
19.30
Mercury, Hg
13.5
 It is the mass per unit
volume of a substance.
Lead is much more dense than iron. So given the
same volume of each, lead will weigh more (have
more mass).
2. Ice (solid) is less dense than water (liquid). Therefore
ice floats on water
1.
Frozen Ice
Liquid Water
 Almost all chemical compounds are least dense in the
gas form and increase in density towards the solid
form.
(Most dense) Solid
Liquid
Gas (Least dense)
 Water densities:
Gas = Least dense
Liquid = Most dense
Solid = Less dense than liquid (in water only!)
 To calculate density you need two things:
 Mass and Volume
D = density
D=
M = mass
V = volume
 Can have several different units:
 kg/l
 g/ml
 g/cm3
M
V
 A softball has a mass of 360 g and a volume of 270 cm3.
Find its density.
Given:
Mass = 360 g
Volume = 270 cm3
Required:
Density (in g/cm3)
Answer :
D = M/V = 360 g / 270 cm3 = 1.33 g/cm3
 https://www.youtube.com/watch?v=ijj58xD5fDI
 We measured the volume of a piece of copper by
displacement in a beaker of water. The initial volume of
water was 21ml and after placing our piece of copper into
the beaker, the new volume was 26ml. Calculate the
density this piece of copper weighing 53.47g.
(remember density = mass / volume)
Mass = 53.47g
Volume = 26 ml-21 ml = 5 ml
Density = 53.47 g = 10.694 g/ml
5 ml
 A pen has what density?
Mass
Volume
25 g
40 mL
280 kg
1.5 m3
77 mg
1.5 mL
2.0 mL
Density
1.5 g/mL
50 g
25 g/L
250 mg
1.0 mg mL
75 kg
55 L
4 kg/L
3.0 L
0.0025 g/ L
200L
200 L
290 g
75 mL
50 g
55 g/mL
200 L
4.0 mg/L
4 000 000 kg/m3
1500 kg
48 g
50 g/L
250 cm3
Mass
Volume
Density
25 g
40 mL
0.63 g/mL
280 kg
1.5 m3
187 kg/m3
77 mg
1.5 mL
51 mg/mL
3.0 g
2.0 mL
1.5 g/mL
50 g
2.0 L
25 g/L
250 mg
250 mL
1.0 mg mL
220 kg
55 L
4 kg/L
0.0075 g
3.0 L
0.0025 g/ L
75 kg
200L
0.38 kg/L
10 000 g
200 L
50 g/L
290 g
75 mL
3.9 g/mL
50 g
0.91 mL
55 g/mL
800 mg
200 L
4.0 mg/L
1500 kg
0.00038 m3
4 000 000 kg/m3
48 g
250 cm3
0.19 g/cm3
 You are going to determine the density of 6 different
objects. (4 provided, 2 you provide)
 Step 1: Find the mass of your object using the
electronic scale (in grams and to 2 decimal places)
 Step 2: We will be using water displacement to
calculate volume.
 Submerge the object in a graduated cylinder filled with
water and note the volume change.
 Volume of object = final volume after displacement –
initial volume before displacement.
 Step 3: Calculate density.
Object
Mass (g) Volume (mL)
Density
(g/mL)
1. Bronze
coloured cube
7.29 g
D=M = 7.29g
V 1 mL
VI = 19 mL
VF = 20 mL
VF-VI = 20-19 = 1 mL
7.29 g/mL
2.
3.
4.
5.
6.
 Matter: Anything that has mass and takes up space.
 Mixture: Two or more substances mixed together.
 Pure Substance: A substance that contains only one
kind of matter.
 Mechanical Mixture: A mixture
of two or more components that
can be seen with the unaided eye.
 Solutions: A homogeneous mixture of
two or more substances.
 Heterogeneous: Consisting of elements
that aren’t all the same (variability).
 Homogeneous: Uniform (the same) throughout.
 Precipitate: The formation of a solid in a solution
during a chemical reaction.
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