This is the phase of matter with no fixed shape or volume.

Gas

Explanation:

Matter exists in three different phases, they are:

- Solid

the phase of matter with fixed shape, high density and non-moving particles that are held together by strong bonds. Example of solids are stone and chalk

- Liquid

the phase of matter with loosely held particles that are held together and take up the shape of the containing vessel. Examples of liquid are water, orange juice

- Gas

This is the phase of matter with no fixed shape or volume, rather its molecules travel rapidly and randomly within the containing vessel. Examples of gases are ammonia and oxygen

Thus, the phase of matter with no fixed shape or volume is known as gas

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