* Density: Density is the key factor here. Density is mass per unit volume.
* Solids vs. Liquids: Solids have their molecules packed tightly together, resulting in higher density. Liquids have more space between molecules, giving them lower density.
Therefore, a given mass of a substance will generally occupy a smaller volume in its solid form than in its liquid form. Since weight is directly related to mass, the weight will be the same in both states.
Exceptions:
There are some exceptions to this rule, mainly due to the unique properties of water:
* Water: Water is unusual because it's less dense in its solid form (ice) than in its liquid form. This is why ice floats. The reason for this is the way water molecules form a crystalline structure in ice, creating more space between them.
To Summarize:
* Generally: A substance will weigh the same in its solid and liquid forms, but its volume will be smaller in solid form.
* Water: Water is a notable exception, as its solid form (ice) is less dense than its liquid form.
Let me know if you have any other questions!
