For example, air with low Mach numbers is treated as an incompressible liquid, while air with high Mach numbers is considered compressible. What is the most compressible gas? Hydrogen gas Why are gases compressible but not liquid? Answer: Gases are compressible because the intermolecular space in gases is very large, while liquids are incompressible because it is smaller in intermolecular spaces.
Why can the liquid be poured easily? The forces between liquid particles are weaker than the forces between solid particles. This means that the liquid particles are further apart and can move more easily.
As the particles can move, the liquid can leak out and take the shape of the container. Are gases compressible? When we apply pressure to a solid or liquid, the volume hardly changes.
Molecular kinetic theory explains why gases are more compressible than liquids or solids. Gases are compressible because most of the gas volume consists of large amounts of empty space between the gas particles.
What is Z in thermodynamics? The compressibility factor Z , also called the compression factor or gas deflection factor, is a correction factor that describes the deviation of a real gas from the behavior of the ideal gas.
It is a thermodynamic property useful for modifying the ideal gas law to take into account the actual behavior of the gas. Envision the water a mile deep in the ocean. At that depth, the weight of the water above, pushing downwards, is about times normal atmospheric pressure Source: University of Illinois at Urbana-Champaign Ask the Van. Even with this much pressure, water only compresses less than one percent.
A waterjet computer-controlled cutting machine using high pressure water to make a decorative pattern in a piece of metal. Yet, in industrial applications water can be tremendously compressed and used to do things like cut through metal especially if an abrasive material is added to the water and the water is hot.
Water being pushed out at tremendous speed through a tiny hole is used in industry to cut through everything from metal to ceramics to plastics and even foods. It is the preferred method when the materials being cut are sensitive to the high temperatures generated by other methods. It has found applications in a diverse number of industries from mining to aerospace where it is used for operations such as cutting, shaping, carving, and reaming. Of course, to cut through stone a stream of water must be moving very fast and producing a tremendous amount of pressure.
Source: NASA. Looking at water, you might think that it's the most simple thing around. Pure water is practically colorless, odorless, and tasteless. But it's not at all simple and plain and it is vital for all life on Earth. Where there is water there is life, and where water is scarce, life has to struggle or just "throw in the towel. In practical terms, density is the weight of a substance for a specific volume. The density of water is roughly 1 gram per milliliter but, this changes with temperature or if there are substances dissolved in it.
The compressibility of a substance is its ability to deform upon application of force. Liquids are not compressible under normal circumstances. The compressibility of a liquid depends upon its intermolecular bond and the spacing between the molecules. In liquid, this spacing is very low. Aside, repulsive forces exist between the molecules.
It is a challenging task to bring the liquid molecules closer, and hence liquids resist compression. Suppose a liquid is kept in a container and a piston is placed at the top. If an immense pressure is applied to the piston, the liquid will compress slightly, as shown in the image below.
Therefore, only under extraordinary circumstances are liquids slightly compressible. In each illustration, we see a very small volume of a material magnified and a simplified representation of the respective bonds within the material.
Below is a more detailed explanation of the different states with references to the illustrations. Solids hold their own shape because the chemical bond, shown as springs between each atom, is relatively strong. However, the like charges of the electrons act to repel the atoms as they get closer together. Conversely, if the atoms move apart, they are pulled back toward each other by the bond. The distance between each atom is very small due to the strength of the bond, but this bond can only hold them together so tight because of the repelling forces.
So when a force is applied to this cube from every direction, the resistance to compression between each atom is very high, this results in minimal compression in the bulk solid. Liquids, on the other hand, have more space between the molecules, allowing them to have more relative motion. Water, for instance, is a polar molecule and exhibits dipole-dipole attraction, as shown by the dotted lines in Figure 1.
The oxygen atom is slightly negative and the two hydrogen atoms are slightly positive. Since these dipole charges are much lower in strength than typical bonds, the Van der Waals forces between molecules are weak and are not constant. Each one may break and be remade many billions of times per second. This is what allows water to flow and yet remain a liquid. The weaker intermolecular forces and higher intermolecular spacing is the reason liquids can be compressed more than solids.
For gases such as nitrogen or air, there are no bonds between molecules at normal temperatures and pressures. Each molecule is moving at a high rate of velocity in various directions. When two gas molecules collide, they rebound off each other with perfect elasticity. There are no losses in the collisions. The intermolecular spacing is too large for intermolecular forces to be significant. At room temperature and standard pressure, the average distance between gas molecules is about ten times the diameter of the molecules themselves.
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