Properties of MatterCh 2

What is Matter?

Matter is anything that:◦ Has mass◦ Takes up space (volume) ◦ Made up of tiny particles called atoms

Mass: ◦ A measure of the amount of matter in an

object

◦ An object’s mass doesn’t really change

◦ This is different than an object’s weight

Weight:◦ A measure of the pull of gravity on an object

◦ Weight can change depending on where you are in the universe!

Measuring Matter

Volume:

◦ A measure of the amount of space an

object takes up (how many particles are in

it)

◦ How do we calculate volume?

Volume = Length x Width x Height

V = L x W x H

For example:15

cm

5 cm20

cm

What is the volume

of this cube in

inches?

Another way to find volume

Volume can sometimes be measured

using water displacement

◦ Water displacement method = putting an

object in a container of water and

measuring how much the water rises

The amount of water displaced will be equal to

the object’s volume

This can only be done with solid objects!

Practice

A rock is dropped into a container of

water. Before the rock was added, the

container had 15 mL of water. Now,

the measurement reads 32 mL of

water.

◦ What is the volume of the rock?

Find the volume of the following

objects: 5 cm

5 cm

5 cm4 in

10

cm

2 in

Density

Density:

◦ A measure of how tightly packed the

particles are in an object

◦ It is the ratio of the mass to its volume

Formula: D=m/V (mass / volume)

For example

D= 400 g / 25 cm3

D= 16g/cm3

Density Practice

What is the density of a box that has a mass of 25 g and a volume of 30 cm3?

A piece of wood measures 3 cm by 6 cm by 4 cm and has a mass of 80 g. What is its density?

A cup of gold colored beads has a mass of 425 g. The volume of the beads is 48 cm3. Given the following densities, what are the beads really made of?

◦ 19.3 g/cm3= gold

◦ 8.86 g/cm3= copper

◦ 9.87 g/cm3= bronze