Matter – Physical Science Unit

States of Matter

Know about the different states of matter? Matters of the heart, money matters and family matters. Well, not exactly! When you talk about states of matter, things actually take a turn towards Physics and Chemistry. And these pertain to matters like solid, liquid and gas.

What is Matter?

Before probing into the depths of matter and its state, it is worthwhile to form a concrete idea about what exactly constitutes matter. Matter is anything that has mass, weight and occupies a definite space. You are a matter and so is your dog. The table and the chairs around you, the water you are drinking and the air you are breathing are all matters. Everything in this world is a matter, the only difference is that they exist in different states.

What are States of Matter?

In Physics, a “state” is a particular phase of matter wherein they exhibit a similar set of features, physical characteristics and chemical compositions to be precise. You may not be always quite sure about the chemical properties, but similarities in physical structures (that is, what the thing looks like, in laymen terms) is apparent enough to convince you that water and beer are somewhat similar and that there’s absolutely nothing common in between that dresser and the fragrance of flowers pervading the air.

There are three commonly recognizable states of matter: solid, liquid and gas. There are some other states of matter or phases that are less common, like plasmas and quark-gluon plasmas, Bose-Einstein and fermionic condensates, liquid crystals, superfluids and supersolids.


A solid matter has a definite shape and volume and a fixed mass. These particular features of a solid arise from the strong intermolecular force existing within it. Because the molecules in a solid form a close-knit group, it is not easy to disintegrate them, either by force or by varying the temperature slightly. You may argue that metals crumple and change shape when heated, but then these are extremely high temperatures that you are considering. You cannot squeeze in a solid into any nook and cranny.


A liquid matter definitely has some mass but it doesn’t have any shape or a definite volume. This is because the molecules within a liquid are not that closely bound like that of solids and it is easier to split them up. And because it is relatively easy to break the bond between the liquid molecules, a liquid matter can take the shape of the container that it is poured in.

However, in this context one thing needs to be mentioned. The intermolecular attraction in a liquid is not too flimsy either. And this gives the liquid matter its definite volume. For instance, you cannot fit in 1-litre of water in a half-litre container. This is something we are all familiar with and you don’t need to conduct an experiment with elaborate apparatus to ascertain it.


In its gaseous state, a matter neither has a definite shape nor a definite volume. This is because the molecules in a gas are very loosely tied, so that it is quite easy to pull them apart. This is why any gas will take on the form of the container it is being pumped into. And not only this, their versatile volume ensures that you can fit in a certain amount of gas in a variety of variously sized containers.

Even a slight change in temperature can bring about massive alterations in the volume of a gas.

Being well up on the fundamental states of matter is the stepping-stone to your understanding of the physical world.