Created By:

Amy Taylor

Hazelwood Central High School

To Teacher Page To Activity

Teacher Page

• Grade Level: 10

• MAP Content Standards:– The learner will be able to describe how the

arrangement and motion of molecules cause different biological, chemical, and physical phenomena.

• Tips for Classroom Use:– Preview the activity before using it with your

class– This activity is recommended for use after the

concepts of density and kinetic molecular theory have been introduced.

• Journaling:– This activity is intended to be used in

conjunction with journaling.– The notebook icon will prompt the students

when to journal in their notebooks.

If you would like to construct a miniature hot air balloon with

your class, there is an excellent website at

http://www.overflite.com/rosebud.html

that gives directions, safety precautions, and even the

calculations involved to make ballooning a memorable learning

event.

Focus on the process of problem solving with your

students… they need to understand not only the facts,

but the reasoning behind them. Have them write their thoughts on paper and then

discuss them as a class.

What makes a hot air balloon float?

You have recently been studying the gas laws...

• In your own words, what does Boyle’s Law mean?

• What does Charles’ Law mean?

• Dalton’s Law?

• These laws are applied in our daily lives…although we are usually completely unaware of their significance.

• One of them can be used to explain how a hot air balloon works.

A Brief History of Ballooning• 1783 several Frenchmen sent up

balloons, and French physicist Jean François Pilâtre made the first human balloon ascent.

• During both the Franco-German War of 1870 and World War I (1914-1918), balloons were used for military observation.

Let’s look at the mechanics involved...

• A propane heater is used to heat the air in a large sack.

• When this happens, the balloon is “filled.”

• The “filled” balloon becomes buoyant and is able to float on air.

• By heating or cooling the air inside the balloon, the balloonist can control the altitude of the balloon.

• Is your hypothesis written as an “if…then” statement?

• Does your hypothesis briefly describe the problem and offer an explanation to explain the situation?

• Discuss your hypotheses with your class.

The Answer...

CHARLES’ LAW! As the TEMPERATURE of the air inside the balloon rises, the

VOLUME increases. When the air particles spread out, the DENSITY of the air inside

the balloon is less than that of the surrounding air and the balloon floats.

How did your hypothesis compare?