What Is Generally True about the Particles in a Liquid (3 Points)

The state of a particular substance is also a physical property. Some substances exist as gases at room temperature (oxygen and carbon dioxide), while others, such as water and mercury metal, exist in liquid forms. Most metals exist as solids at room temperature. All substances can exist in one of these three states. Figure (PageIndex{2}) shows the differences between solids, liquids and gases at the molecular level. A solid has a certain volume and shape, a liquid has a certain volume but no particular shape, and a gas has neither a certain volume nor a certain shape. Solids usually have their constituent particles, which are arranged in a regular, three-dimensional arrangement of alternating positive and negative ions called a crystal. The effect of this regular arrangement of particles is sometimes macroscopically visible, as shown in figure (PageIndex{3}). Some solids, especially those made up of large molecules, cannot easily organize their particles into such regular crystals and exist as amorphous (literally “shapeless”) solids. Glass is an example of an amorphous solid.

On the other hand, through contemporary research into a unified field theory that would place three of the four types of interactions between elementary particles (strong force, weak force, and electromagnetic force, not just gravity) within a single conceptual framework, physicists may be about to explain the origin of mass. Although a completely satisfactory great unified theory (GUT) has not yet been derived, one component, the electroweak theory of Sheldon Glashow, Abdus Salam, and Steven Weinberg (who received the Nobel Prize in Physics in 1979 for this work), predicted that an elementary subatomic particle known as the Higgs boson would give mass to all known elementary particles. After years of experimentation with the most powerful particle accelerators available, scientists finally announced the discovery of the Higgs boson in 2012. For detailed treatments of the properties, states and behaviour of bulk solids, see solids, liquids and gases as well as specific shapes and types such as crystal and metal. If the particles of a substance have enough energy to completely overcome intermolecular interactions, the particles can separate from each other and move randomly through space. This describes the state of the gas, which we will examine in more detail elsewhere. Like liquids, gases do not have a specific shape, but unlike solids and liquids, gases also do not have a specific volume. The transition from solid to liquid usually does not significantly change the volume of a substance. However, switching from a liquid to a gas significantly increases the volume of a substance by a factor of 1,000 or more. Gases have the following properties: Matter generally exists in one of three states: solid, liquid, or gaseous. The state of a particular substance is also a physical property. Some substances exist as gases at room temperature (oxygen and carbon dioxide), while others, such as water and mercury metal, exist in liquid forms.

Most metals exist as solids at room temperature. All substances can exist in one of these three states. In addition to its existence in one of the three states, matter can also undergo a change of state. A change of state occurs when matter is transformed from one state to another, para. B example when a liquid is converted into gas or a solid is converted into liquid. If we cooled liquid mercury to its freezing point of (-39^text{o} text{C}), we would find under the right pressure conditions that all liquid particles would pass into the solid state. Mercury can solidify when its temperature is brought back to freezing. However, when mercury returns to room temperature, it does not exist in the solid state for long and returns to its most common liquid form. Water can take many forms. At low temperatures (below 0°C), it is a solid. At “normal” temperatures (between 0°C and 100°C) it is a liquid. At temperatures above 100°C, water is a gas (steam).

If we heat liquid mercury to its boiling point of (357^text{o} text{C}) under the right pressure conditions, we would find that all particles in the liquid state pass into the gaseous state. At the most elementary level, matter consists of elementary particles called quarks and leptons (the class of elementary particles that includes electrons). Quarks combine to form protons and neutrons and, together with electrons, form atoms of periodic table elements such as hydrogen, oxygen and iron. Atoms can further combine to form molecules such as the water molecule H2O. Large groups of atoms or molecules, in turn, make up most of everyday life. If the particles of a substance have enough energy to partially overcome intermolecular interactions, the particles can move around each other while remaining in contact. This describes the liquid state. In a liquid, the particles are always in close contact, so the liquids have a certain volume. However, since particles can move quite freely around each other, a liquid has no specific shape and takes on a shape dictated by its container. The concept of matter is further complicated by quantum mechanics, whose roots go back to Max Planck`s explanation of the properties of electromagnetic radiation from a hot body in 1900.

From a quantum perspective, elementary particles behave both as tiny spheres and as waves propagating in space – an apparent paradox that has not yet been fully resolved. Additional complexity in the importance of matter comes from astronomical observations that began in the 1930s and show that much of the universe is composed of “dark matter.” This invisible material does not affect light and can only be detected by its gravitational effects. Its detailed nature remains to be determined. In the solid, the individual particles of a substance are in fixed positions relative to each other because there is not enough thermal energy to overcome the intermolecular interactions between the particles. As a result, solids have a certain shape and volume. Most solids are hard, but some (like waxes) are relatively soft. Many solids made of ions can also be quite fragile. Depending on temperature and other conditions, matter can occur in one of the following states. At normal temperatures, for example, gold is a solid, water is a liquid, and nitrogen is a gas as defined by certain properties: solids retain their shape, liquids take the form of the container that contains them, and gases fill an entire container. These states can be classified into subgroups. Solids can, for example, be divided into those with crystalline or amorphous structures or into metallic, ionic, covalent or molecular solids depending on the types of bonds that hold the constituent atoms together. Less clearly defined states of matter include plasmas, which are ionized gases at very high temperatures; foams that combine aspects of liquids and solids; and clusters, which are collections of a small number of atoms or molecules that have both atomic and mass properties.

Although basic ideas about matter date back to Newton and even earlier to Aristotle`s philosophy of nature, in the early 20th century, a deeper understanding of matter began to emerge with new mysteries. Einstein`s (1905) theory of special relativity shows that matter (in mass) and energy can be converted into each other according to the famous equation E = mc2, where E is energy, m mass and c is the speed of light. This transformation takes place, for example, during nuclear fission, in which the core of a heavy element such as uranium divides into two fragments of smaller total mass, releasing the mass difference as energy. .