The statement is true.
Gases have the ability to expand infinitely under the right conditions because the particles are far apart and move freely. They occupy whatever volume is available to them. Unlike solids and liquids, which have fixed volumes, gases do not have a definite shape or volume. When a gas is placed in a container, it expands to fill the entire space available.
However, it’s important to note that while gases can expand infinitely in the theoretical sense, practical limitations do exist due to factors like pressure and temperature. In a closed system, for instance, increasing the volume will decrease the pressure of the gas until it reaches an equilibrium. In the vacuum of space, gases continue to disperse until there is no distinction between the gas and the vacuum. Therefore, while gases can expand indefinitely, the underlying physical conditions will dictate how this is observed in reality.