* State of Matter: The answer depends entirely on the state of matter of the substance.
* Gases: Gases will always expand to fill their container, so 1 gram of a gas will occupy the entire 1-liter volume.
* Liquids: Liquids have a fixed volume, so 1 gram of a liquid will only occupy the volume corresponding to its density. You'd need to know the density of the specific liquid to determine if 1 gram would fill the container.
* Solids: Solids have a fixed shape and volume. 1 gram of a solid would likely not even come close to filling a 1-liter container.
* Density: Even within the same state of matter, density plays a crucial role. A substance with a higher density will occupy less volume for the same mass.
Examples:
* Gas: 1 gram of helium gas will occupy the entire 1-liter container.
* Liquid: 1 gram of water will only occupy 1 milliliter (0.001 liters) because water's density is 1 gram per milliliter.
* Solid: 1 gram of iron would be a very small piece and would not come close to filling a 1-liter container.
To give you a specific answer, you would need to tell me the substance and its state of matter.