Density Notes Key

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Name: _____________________________________________________ Period _________
Density
Kaspriskie
DENSITY
Density =
𝒎𝒂𝒔𝒔
𝒗𝒐𝒍𝒖𝒎𝒆
or
D=
𝒈𝒓𝒂𝒎𝒔
𝟏 𝒄𝒎
https://www.youtube.com/watch?t=142&v=kE8I_M2pyg8
1. Calculating density with known mass and volume:
a. determine the density of a material that has a mass of 36.5g and volume of 2.55 cm3.
D = m = 36.5g = 14.3 g/cm3
v
2.55 cm3
b. find the density of a 25g object that displaces 7.5mL of water. (1 mL = 1 cm3)
D = m = 25g = 3.3 g/mL
V 7.5mL
2. Calculating mass with known volume and density:
a. find the mass of 52.2mL of olive oil if the density of olive oil is 0.833g/mL.
m = D X V = 0.833g/mL X 52.2mL
m = 43.5g
b. find the mass of 25.9cm3 of gold if the density of gold is 19.0 g/cm3.
m = 19.0g/mL X 25.9mL
m = 492g
3. Calculating volume with known density and mass:
Find the volume of a 125g bar of gold. (density is 19.0 g/cm3)
v = m = 125g
D
19.0 g/cm3
v= 6.58mL
4. Density is a physical property. It can be used to help identify a substance. Example: the density of
aluminum is 2.7g/cm3. A 22g metal rod displaces 4.5mL of water. Is the rod aluminum? (1 mL = 1 cm3)
D = m = 22g = 4.9 g/mL  does not equal 2.7g/mL so it is NOT aluminum
v
4.5mL
Density Problems Practice
Complete the following density problems.
 SHOW ALL WORK!! Include the PROPER UNITS in your final answers.
1. The density of lead is 11.4 g/cm3. What is the mass of a piece of lead that has a volume of 18.5cm3?
210.9 g
2. What is the volume of a sample of cough syrup that has a mass of 53.7 g? Then density of cough syrup is
0.95 g/cm3.
56.53 mL
3. Aspirin has a density of 1.4 g/cm3. What is the mass of a 25 mL sample of aspirin? (1 mL = 1 cm3)
35 g
4. A cup of gold colored metal beads was measured to have a mass 425 g. By water displacement, the volume of the
beads was calculated to be 48.0 mL. Given the following densities, Gold: 19.3 g/ cm3; Copper: 8.86 g/ cm3; Bronze: 9.87
g/ cm3, identify the metal. Show your work. (1 mL = 1 cm3)
8.85 g/cm3 = COPPER
5. When a sample of a metal alloy that has a mass of 9.4g is placed into a graduated cylinder containing water, the
volume reading in the cylinder increases from 16.0 mL to 19.5 mL. What is the density of the alloy sample in grams per
mL?
(Volume: 19.5mL - 16.0 mL = 3.5 mL)
2.69 g/mL
6. In the boxes below (all the same size), the dark circles represent particles of matter (each particle has the same mass).
Which box has the greatest density? EXPLAIN.
C
Highest ratio of mass per volume
A
B
7. Determine the density of the metal bar below if it’s mass is 855g.
(volume = LXWXH)  14.2 X 10.9 X 2.12 = 328.13 cm3
2.61g/cm3
C
D
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