3. Mass: the amount of matter in an object
Measured using metric units (grams or kilograms)
You can use a pan balance to
measure mass
Which block has more mass?
Mass and weight aren’t the same
Weight is the measure of gravity’s pull on you
▪ Your weight on the moon is 1/6 your weight on Earth
▪ How much would someone weigh on the moon if they weighed 120
pounds on Earth?
▪ It doesn’t matter if you are on the Earth or the moon, your mass stays
the same
4. Volume: the amount of space taken up by an
object
You can measure the volume of solids, liquids, and
gases
▪ V = length × width × height
▪ V = 5 cm × 4 cm × 3 cm
▪ V = 20 × 3
▪ V = 60 cm³
5. 1. Fill a beaker or graduated cylinder with
water and note the volume
2. Then, place the object in the beaker or
graduated cylinder
3. Note the new reading and find
the difference between the
two volumes
23 – 20 = 3 cm³
20 mL
23 mL
volume of the rock
6. Liquids have a definite volume, but they take
the shape of their containers
These two glasses of orange juice look
different but they contain the same volume
of juice!
7. Gases spread out to fill
their containers
The volume of gas is the
same as the size of its
container
8. Density: the measurement of how
heavy something is for its size
Density = Mass ÷ Volume
D = 180 g ÷ 60 cm³
D = 3 g/ cm³
Volume = 60 cm³
Mass = 180 g
9.
10. Atoms: the smallest parts that make up matter
Protons: exist in the center, or nucleus, of an atom
▪ Have a positive charge
▪ The number of protons identifies the atom (atomic number)
Neutrons: exist in the center, or nucleus, of an atom
▪ Have no charge (neutral)
Electrons: move around the nucleus of an atom
▪ Have a negative charge
Everything is made up of atoms!