## Colored Clouds

### Melissa Lee Herring

#### Description

In this lesson learners will observe particles that make up warm water move around faster than particles that make up cold water. This will be demonstrated by observing clouds made of food coloring mixed with different temperatures of water.

#### Objectives

The student understands that heating or cooling of matter will speed up or slow down, respectively, the motion of the small particles within matter and that this is what causes a phase change.

#### Materials

Each pair of students will need the following:
-Three clear cups
-Food Coloring
-Room Temperature Water
-Warm Water
-Cold Water
-Science Logs for Each Student

#### Preparations

1. Warm water on hotplate or in microwave. Be sure that water is a touchable temperature before giving to students.
2. Cool water by dissolving ice in room temperature water. Make sure that the water is cold to the touch, like a refridgerated drink.
3. Place students in pairs and prepare one cold, one warm, and one room temperature clear cup of water for each pair.
4. Distribute food coloring (one color per pair).
5. Distribute Science Logs.

#### Procedures

1. Students work in pairs. One student closes his eyes while the other student provides a cup of water for the first student to dip his finger in. The student with his eyes closed identifies the temperature of the water by saying, "warm, cold, or room temperature."

2. The students switch.

3. Students should discuss what makes the waters different.

4. In science logs the students hypothesize as to what makes the water temperatures different.

5. Students line up their cups one next to the other.

6. Students drop three drops of food coloring in the cold water and observe and record the dispersement. **In the cold water the coloring basically falls to the floor of the cup. This is because the cold water has less energy and the particles are in motion, but not 'busy'.

7. Students drop three drops of food coloring in the room temperature water and observe and record the dispersement. In the room temperature water, the coloring mixes at a slow pace but the movement of particles is observable.

8. Students drop three drops of food coloring in the warm water and watch the dispersement. They notice that in the warm water, the food coloring mixes itself into the water rapidily. **Students actually see the color swirling. This is due to the particles that make up water moving more rapidly due the increased energy that causes the heat of the water.**

9. After observations and recordings are made students illustrate their findings (one illustration for each cup) in their science logs.

10. Throughout this activity the teacher circulates, reads hypotheses, answers questions, and works with pairs to explain the scientific rule behind this activity.

Special Note: To explain the 'phase change' of this benchmark give the example of boiling water (liquid) turning into steam (gas). The phase change is produced by enough energy/heat creating the particles that the matter (water) is made up of so that the particles move around in quick, circular motions. This behavior eventually produces the phase change from a liquid (water) to gas (steam). The opposite occurs in explaining how water (liquid) becomes ice (solid). With enough cooling, the energy is reduced and the particles slow down enough to produce the solid (ice).

#### Assessments

In their science logs students correctly explain and illustrate that they understand that heating or cooling of matter will speed up or slow down, respectively, the motion of the small particles within matter.

#### Extensions

The ESOL or ESE student can illustrate the different observations.