States of matter The three different forms

States of matter the three different forms in which matter can exist solid, liquid, and gas. 

Substances, and matter in general, come in different forms, called states of matter. The three most common states of matter are solid, liquid, and gas ... 

Monomolecular films may exist in many different forms, which correspond, in the two dimensions of the surface, to the three principal states of matter in three dimensions, solid, liquid, and gaseous. The principal factor determining whether or not the films are stable is the strength of the anchorage of the molecules to the surface, an attraction perpendicular to the surface the principal factors deciding the state of the surface films... 

A sample of matter can be a gas, a liquid, or a solid. These three forms of matter are called Ihe states of matter. The states of matter differ in some of their simple observable properties. A gas (also known as vapor) has no fixed volume or shape ralher, it conforms to the volume and shape of its container. A gas can be compressed to occupy a smaller volume, or it can expand to occupy a larger one. A liquid has a distinct volume independent of its container but has no specific shape It assumes the shape of the portion of the container fiiat it occupies. A solid has both a definite shape and a definite volume It is rigid. Neither liquids nor solids can be compressed to any appreciable extent. 

The next concept which we wish to examine is that of the differences between the three states of matter, gases, liquids and solids. In this case, we will find very significant differences in their energy content, namely that the gaseous form is the most energetic while the solid has the least energy. 

In the thermodynamic sense, a phase is defined as part of a chemical system in which all the material has the same composition and state. Appropriately, the word comes from the Greek phasis, meaning appearance . Ice, water and steam are the three simple phases of H20. Indeed, for almost all matter, the three simple phases are solid, liquid and gas, although we must note that there may be many different solid phases possible since H20(S) can adopt several different crystallographic forms. As a related example, the two stable phases of solid sulphur are its monoclinic and orthorhombic crystal forms. 

You have only to think about water to appreciate how different the three states of matter are. Flying, swimming, and ice skating are all done in contact with water in its various forms. Clearly, the arrangements of the water molecules must be significantly different in its gas, liquid, and solid forms. 

W e have already pointed out that the military term smoke comprehends two b Lsically different phenomena (1) an aerial concentration of minute solid particles resulting from combustion, and (2) an aerial concentration of minute liquid particles resulting from chemical reactions not involving combustion. Neither of these phenomena can be scientifically clasafied into any of the three standard physical states of matter. On the contraiy, both are dispersed forms of matter, known as coUoidid stispensions or solutions. 

The Greek philosopher who started this transformation was Thales of Miletus. Information about him is limited, and what we know comes to us from later writers, since no texts by him have survived. He was probably born about 623 b.c.e., in Ionia, which is in modem Turkey. Thales was believed to have traveled widely and likely visited Egypt and studied in Greece. He conceived of the world as a sphere floating in an eternal sea and argued that water was the most fundamental element. It came in three forms water, earth, and mist. This was an important philosophical insight, since it demonstrated an understanding of the states of matter (solid, liquid, and gas, in modem terms) in addition to different types of matter. 

We begin by examining different types of solutions that can be formed from the three states of matter solid, liquid, and gas. We also characterize a solution by the amount of solute present as unsaturated, saturated, and supersaturated. (12.1)... 

The most important multicolour display technology in current use involves liquid crystal displays (LCDs), which overtook CRTs in popularity around the mid-2000s. Liquid crystals (LCs), commonly referred to as the fourth state of matter, are materials that are intermediate in character between the crystalline solid and liquid states.Unlike normal isotropic liquids in which the molecules essentially adopt a randomised orientation, liquid crystals show some time-averaged positional orientation of the molecules. In this sense, they resemble solid crystalline materials, although they retain most of the properties of liquids, notably the ability to flow. They are formed most commonly from molecules with rod-like geometry, which are referred to as calamitic. These molecules may orientate in various ways to form different types of LC phases [mesophases). There are three main mesophase types smectic, nematic and chiral nematic. In the smectic mesophase, as illustrated in Figure 11.1(a), the molecules are arranged in raft-like layers with their molecular axes parallel. These layers can pass over each other as the material flows. In the... 

The property of forming solutions or homogeneous mixtures of varying composition, is a very important one, and is met with in all three physical states of matter, gaseous, liquid, solid. Of the different possible kinds of solutions, the most important are those formed by the solution of a gas in a liquid, of a liquid in a liquid, and of a solid in a liquid. 

Under ordinary conditions, matter exists in three different physical forms called the states of matter—solid, liquid, and gas. Solid matter has a definite shape and a definite volume. A solid is rigid and incompressible, so it keeps a certain shape and cannot be squeezed into a smaller volume. A solid has these properties because the particles that make up the solid are packed closely together and are held in a specific arrangement. 

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