Student Exploration: Boyle’s Law and Charles’s Law

Vocabulary: absolute zero, Boyle’s law, Charles’s law, Gay-Lussac’s law, Kelvin scale, pressure

Prior Knowledge Question (Do this BEFORE using the Gizmo.)

A small helium tank measures about two feet (60 cm) high. Yet it can fill over 50 balloons! How

can such a small tank contain enough helium to fill so many balloons?

The small container can hold all that helium in the container because the gas in the tank is

 under a lot of pressure

Gizmo Warm-up

The Boyle’s Law and Charles’s Law Gizmo shows a container

of gas. Inside, small purple spheres represent gas molecules.

1. Observe the particles. Are they all moving at the same

speed? Yes they are all moving at the same speed.

2. How do the particles interact with the walls and lid of the container?

The bounce off the walls and lid while providing pressure

These interactions contribute to the pressure on the walls of the container. Pressure is

defined as force per unit area. The SI units of pressure are newtons per square meter

(N/m2

), or pascals (Pa).

3. Slowly drag the temperature (T) slider back and forth. (Note: In this Gizmo, the Kelvin scale

is used to measure temperature. On the Kelvin scale, 0 degrees is absolute zero, the

coldest possible temperature. Absolute zero is equal to -273.15 °C or -459.67 °F)