Particulate Theory of Matter

MATTER

Open Ended

What do you observe when I add food coloring to water?

Food Coloring in Water

• What can you conclude about water based

on observing food coloring in water?

Particles

1. All matter is made of

extremely small particles
called atoms or molecules.

2. The particles are always in

motion.

1. All matter is made of extremely

small particles called atoms or

molecules.

• In about 1 tablespoon of water, there are

about 200,000,000,000,000,000,000,000
molecules of water

2. The particles are always in motion.

• How do your observations support the idea

that the particles (molecules) in water are in
motion?

• The water particles move and push the color

in all directions. The particles of the food
coloring themselves are also in motion.

2. The particles are always in motion.

• This is a model of water particles. The

particles are not in any exact order but are
near each other. They have little curved
“motion lines” to show that the particles are
moving.

2. The particles are always in

motion

• Using circles and “motion lines” to represent

water particles, draw a model of water on the
particle level. Be sure to show that water
particles are:
– Randomly arranged
– Close together
– Moving

Multiple Choice

All matter is made of tiny particles called _________ or ____________.

• cells or atoms

• bacteria or molecules

• atoms or molecules

• cells or tissue

3. The particles of matter
(atoms and molecules) are
attracted to each other.

Surface Tension

Poll

Ms. King placed a thermometer in a jar of very hot water. Her students watched what happened to the thermometer. Immediately the level of the red liquid went up. Her students disagreed about why the red liquid in the thermometer rose when the thermometer was placed in hot water. Choose which students reasoning you most agree with:

• The hot water pushed it up.

• The number of molecules in the red liquid increased.

• The heat inside the thermometer rises.

• The molecules of red liquid are further apart.

• The molecules of the red liquid are getting bigger.

Temperature and

Matter

Open Ended

Observe when food coloring is added to hot and cold water. What does the speed of the mixing tell you about the speed of molecules in hot and cold water?

Temperature

• Temperature is a measure of the (average)

movement of molecules in a substance.

➢As temperature increases, the energy of

motion increases.

➢Meaning that the atoms move more quickly.

➢Because the atoms move more quickly, most

substances expand when heated.

Multiple Choice

If you heat a substance, the particles of the substance will move....

• more slowly

• more quickly

• not change their motion

4. More heat energy = more

particle motion

5. More particle motion = more

spread out (expanded)

Particle Theory

The Particle Theory of Matter

1. Matter is made of tiny particles called atoms

and molecules

2. Particles of matter are attracted to each

other

3. The particles of matter are always in motion
4. More heat energy = more particle motion
5. More particle motion = more spread out

Poll

Ms. King placed a thermometer in a jar of very hot water. Her students watched what happened to the thermometer. Immediately the level of the red liquid went up. Her students disagreed about why the red liquid in the thermometer rose when the thermometer was placed in hot water. Choose which students reasoning you most agree with:

• The hot water pushed it up.

• The number of molecules in the red liquid increased.

• The heat inside the thermometer rises.

• The molecules of red liquid are further apart.

• The molecules of the red liquid are getting bigger.

Open Ended

Why does a substance expand when it is heated?