Which statement best describes the primary characteristic of a gas that distinguishes it from a liquid?

A gas has a fixed shape, while a liquid does not.

A gas has a definite volume, while a liquid does not.

A gas does not have a definite volume, while a liquid does.

A gas is always visible, while a liquid is always colorless.

Based on the property of expansion, what can be inferred about the movement of gas molecules within a sealed container?

The molecules are arranged in a fixed, orderly pattern.

The molecules are in constant motion, causing them to spread out.

The molecules slide past one another but remain in a defined volume.

The molecules only vibrate in place and do not travel far.

The volume cannot be determined without knowing the temperature.

An ice cube melting into water in a glass.

Pouring sand from a bucket into a sandbox.

Inflating a bicycle tire with an air pump.

A sugar cube dissolving in a cup of hot tea.

The air will form a small pocket at the bottom of the tank.

The air molecules will spread out to occupy the entire volume of the tank.

The air will remain concentrated near the valve where it was pumped in.

The air will rise and form a thin layer at the very top of the tank.