Focus Question: How Does Cooling and Heating Affect the Level of Water in the Pipe?

Chemical Interactions: Investigation 4.2: Liquid Expansion

Focus Question: How does cooling and heating affect the level of water in the pipe?

Procedure:

a.Write the focus question in your notebook.

b.Make a thermometer:

1.Push the clear plastic pipe a short distance into the rubber stopper.

2.Use a syringe to put 35 mL of blue water into the glass bottle.

3.Push the stopper into the bottle as far as it will go. Use the pipette tofine-tune the water level so it is halfway up the pipe.

4.Tape a 1” ✕ 3” card to the clear tube. Label the water level “R.”

5.In your notebook, record the starting temperatures of the cold and hot water.

6.Place the bottle in cold water. After 3 minutes, label the waterlevel “C.”

7.Move the bottle to hot water. In 5 minutes, label the water level “H.”

c.In your notebook draw and explain what happened when you placed the bottle system in cold water? In hot water?

d.Discuss the following with your partner:

• What do you think caused the water to go up in the pipe?
• What do you think caused the water to down in the pipe?

e.Answer the focus question in your notebook.

Language Objective:

Students construct a bottle system toobservethe effect of heating and cooling water, and build an explanation and a model to describeexpansion and contraction in terms of kinetic energy.

English Language Development:

• Explain that kinetic energy is energy in motion. The speed at which particles move is directly related to the amount of kinetic energy it has.

• Review the discussion questions with students:
• Water expands when the kinetic energy of its particles increases.
• Water contracts when the kinetic energy of its particles decreases.

• Students draw their bottle systems in hot water and cold water, and draw what they think the water particles would look in both. Then they write an explanation to go with each picture. For students who need scaffolding, provide sentence frames such as:

When water is ______, it ______, because ______.

When water is ______, it ______, because ______.

Essential Question: What are water’s unique physical and chemical properties?

Application at Grades 6 & 8: How is the heat capacity of water different from other materials? How does the heat capacity of water affect weather?

TEKS for Physical Science 6th: investigate methods of thermal energy transfer, including conduction, convection, and radiation; verify through investigations that thermal energy moves in a predictable pattern from warmer to cooler until all the substances attain the same temperature.

TEKS for Earth Science8th: Recognize that the Sun provides the energy that drives convection within the atmosphere and oceans, producing winds and ocean currents.

TEKS for ELL’s:

• Vocabulary needs to be taught in the context of connected discourse so that language is meaningful.
• At the same time ELL’s are learning in English, the focus is on academic English, concepts, and the language structures specific to the content.

Velez & Vargas LHS 2011