Why are, say, water and Carbon Dioxide in different states (liquid/gas) at the same temperature...?

Question

....if the energy/temperature of the molecules determines the state of the matter? I apologise for the naivety of the question.

Answer 1

The states of matter are more to do with the strength of the attraction between atoms/molecules of the substance than anything else. The energy level (temperature) of a substance must be above a certain level before the attraction can be partially overcome (solid to liquid) or completely overcome (liquid to gas, or solid to gas).

Carbon dioxide molecules don't form terribly strong bonds between themselves and at room temperature they have more than enough energy to overcome these bonds completely and become a gas. Water forms unusually strong bonds between its molecules for such a small molecule and so remains a liquid at room temperature.

Answer 2

Hi. Two things. Water at 32F and ice at 32F are in two phases at the same temperature. If you are asking why water and CO2 are different at the same temperature, it has to do with the bond strength of the molecules. Hydrogen Dioxide and Carbon Dioxide have different bond strengths. (This is by example only. Those are not technical terms.)

Answer 3

the state of material depends on the nature of it,for e.g water is liquid caz the forces between moleculs of it makes a liquied however if u heat it ,it affects on forces and make them weaker then it becomes vapore,another example is NaCl it is solid caz the ioninc forces between Na and Cl is vary strong...u should heat it alot if u want a melted NaCl...
the forces between moleculs and atoms and ions are so diffrent for more information u should study books abt it...I hope I could helped u...