Name:
Aim 7: What is density?
Date:
A. Let’s review MASS and VOLUME:
HOW DO WE MEASURE IT?
TOOLS USED
UNITS
MASS
VOLUME
B. DENSITY: reflects how closely packed the particles of matter are.
1. DEFINITION:
2. UNITS:
3. FORMULA:
(D) DENSITY
(M) MASS
(V) VOLUME
Density =
Mass =
Volume =
D=
M=
V=
cover the letter that is your “unknown”
to figure out your formula
4. DENSITY FACTS:
a. The HOTTER the liquid, the LESS dense it is
b. If you cut an object in HALF it is still the SAME DENSITY
c. *WATER’S DENSITY* = ___________________________________
What happens when objects are placed in water?
Objects > 1g/mL
Objects < 1g/mL
HOW TO SOLVE DENSITY PROBLEMS IN 4 STEPS!
Ex: A piece of wood has a mass of 18.2 grams and a volume of 30.6 cm3. What is the density of the wood?
1. Write the FORMULA you are going to use
D = M/V
2. PLUG in your “known” values using the appropriate units
D = 18.2 g / 30.6 cm3
3. SOLVE for your “unknown.” Include your units!
D = 556.92 g/cm3
4. ROUND your answer to the nearest TENTH. Include your units!
D = 556.9 g/cm3
Fill in the blanks with: (1) The proper formula, (2) ALL work SHOWN in the mass, volume or density space for
each question (3) Round answers to the nearest TENTH and Give appropriate units for your answers in g,
cm3 or g/cm3, (4) Place an X in the column if the substance will float or sink in water
FORMULA
MASS
VOLUME
12 g
.5 cm3
DENSITY
1
2
16 g
.2 g/ cm3
3
5 cm3
20 g/ cm3
4
.9 g
.3 g/ cm3
5
6g
4 cm3
8g
1.8 cm3
6
7
13 cm3
9 g/ cm3
8
14.7 g
15 cm3
9
2 cm3
1.1 g/ cm3
10
17 g
3 g/ cm3
SINK
FLOAT
CALCULATING THE DENSITY OF SOLIDS
1. Determine the mass using a triple beam balance or a scale
2. Determine the volume
a. Regularly shaped object: l x w x h using a ruler.
b. Irregularly shaped object: water displacement method