Higher kinetic energy causes particles to vibrate or move around faster Show Explanation:Solids have the lowest kinetic energy so vibrate very little. It would be a gas, because they lack the intermolecular forces that hold liquids together, and the rigidity that holds solids together. This example of water pretty much summarizes it:  Solids, in general, are rigid. They are known to have a definite form, definite volume. Hence, their kinetic energy is smaller than that of loose fluids. Ice is a convenient example: A liquid, on the other hand, is generally more free-form - an indefinite form, but still a definite volume, as they aim to take the shape of their container. Their intermolecular forces hold them together, such as the hydrogen-bonding networks in water, but that limits their motion less so than in comparable solids, as intermolecular forces aren't full bonds. Although in water, let's say, proton-jumping throughout the water clusters is fair-game, the water molecules aren't as free to scatter into the air and disperse as in a gas. So, liquids have kinetic energies in between that of a comparable solid and gas. Gases are free to move - they aren't necessarily lighter than air, per se, but they are expected to lack the intermolecular forces that hold liquids together, so they are more freely-moving. Again:
Hence, gases have more kinetic energy than comparable liquids, and those have more kinetic energy than comparable solids. The three basic states of matter have different amounts of kinetic (movement) energy: in a solid, the particles vibrate about a fixed point. If you add heat energy to a solid, the particles will vibrate with larger and larger amplitudes ('wobbles') and eventually more and more of these particles will be able to break their solid bonds to form a liquid (melting). Liquids have more kinetic energy than solids. If you add heat energy to a liquid, the particles will move faster around each other as their kinetic energy increases. Some of these particles will have enough kinetic energy to break their liquid bonds and escape as a gas (evaporation). Even water in a puddle on a cool day has some particles with enough energy to break their liquid bonds and become a gas. There will be enough of these particles so that after several hours the puddle has evaporated into a gas. GCSE Physics Keywords: Kinetic energy, Solid bonds, Liquid bonds, Vibrate, Heat energy, Breaking bonds, Melting, Evaporation. Course overview Liquids The Structure of Liquids The difference between the structures of gases, liquids, and solids can be best understood by comparing the densities of substances that can exist in all three phases. As shown in the table below, the density of a typical solid is about 20% larger than the corresponding liquid, while the liquid is roughly 800 times as dense as the gas. Densities of Solid, Liquid, and Gaseous Forms of Three Elements
The figure below shows a model for the structure of a liquid that is consistent with these data. The key points of this model are summarized below.
What Kinds of Materials Form Liquids at Room Temperature? Three factors determine whether a substance is a gas, a liquid, or a solid at room temperature and atmospheric pressure:
When the force of attraction between the particles are relatively weak, the substance is likely to be a gas at room temperature. When the force of attraction is strong, it is more likely to be a solid. As might be expected, a substance is a liquid at room temperature when the intermolecular forces are neither too strong nor too weak. The role of atomic or molecular weights in determining the state of a substance at room temperature can be understood in terms of the kinetic molecular theory, which includes the following assumption: The average kinetic energy of a collection of gas particles depends on the temperature of the gas, and nothing else. This means that the average velocity at which different molecules move at the same temperature is inversely proportional to the square root of their molecular weights. Relatively light molecules move so rapidly at room temperature they can easily break the bonds that hold them together in a liquid or solid. Heavier molecules must be heated to a higher temperature before they can move fast enough to escape from the liquid. They therefore tend to have higher boiling points and are more likely to be liquids at room temperature. The relationship between the molecular weight of a compound and its boiling point is shown in the table below. The compounds in this table all have the same generic formula: CnH2n+2. The only difference between these compounds is their size and therefore their molecular weights. Melting Points and Boiling Points of Compounds with the Generic Formula CnH2n+2 As shown by the figure below, the relationship between the molecular weights of these compounds and their boiling points is not a straight line, but it is a remarkably smooth curve. The data in the figure below show how the shape of a molecule influences the melting point and boiling point of a compound and therefore the probability that the compound is a liquid at room temperature. The three compounds in this figure are isomers (literally, "equal parts"). They all have the same chemical formula, but different structures. One of these isomers Pentane and isopentane molecules have zigzag structures, which differ only in terms of whether the chain of C-C bonds is linear or branched. These less symmetrical molecules are harder to pack to form a solid, so these compounds must be cooled to much lower temperatures before they become solids. Pentane freezes at -130oC. Isopentane must be cooled to almost -160oC before it forms a solid. The shape of the molecule also influences the boiling point. The symmetrical neopentane molecules escape from the liquid the way marbles might pop out of a box when it is shaken vigorously. The pentane and isopentane molecules tend to get tangled, like coat hangers, and must be heated to higher temperatures before they can boil. Unsymmetrical molecules therefore tend to be liquids over a larger range of temperatures than molecules that are symmetrical.
Vapor Pressure A liquid doesn't have to be heated to its boiling point before it can become a gas. Water, for example, evaporates from an open container at room temperature (20oC), even though the boiling point of water is 100oC. We can explain this with the diagram in the figure below. The temperature of a system depends on the average kinetic energy of its particles. The term average is in this statement because there is an enormous range of kinetic energies for these particles. Even at temperatures well below the boiling point of a liquid, some of the particles are moving fast enough to escape from the liquid. When this happens, the average kinetic energy of the liquid decreases. As a result, the liquid becomes cooler. It therefore absorbs energy from its surroundings until it returns to thermal equilibrium. But as soon as this happens, some of the water molecules once again have enough energy to escape from the liquid. In an open container, this process continues until all of the water evaporates. In a closed container some of the molecules escape from the surface of the liquid to form a gas as shown in the figure below. Eventually the rate at which the liquid evaporates to form a gas becomes equal to the rate at which the gas condenses to form the liquid. At this point, the system is said to be in equilibrium (from the Latin, "a state of balance"). The space above the liquid is saturated with water vapor, and no more water evaporates.
The pressure of the water vapor in a closed container at equilibrium is called the vapor pressure. The kinetic molecular theory suggests that the vapor pressure of a liquid depends on its temperature. As can be seen in the graph of kinetic energy versus number of molecules, the fraction of the molecules that have enough energy to escape from a liquid increases with the temperature of the liquid. As a result, the vapor pressure of a liquid also increases with temperature. The figure below shows that the relationship between vapor pressure and temperature is not linear
Why do gases have more kinetic energy than liquids?The kinetic energy of molecules is highest in gases because molecules in gases have more space between them and they observe the less intermolecular force on each other and move with higher velocity and due to higher velocity in the process higher energy.
Does liquid have high kinetic energy?The particles in a liquid have more kinetic energy than the particles in the corresponding solid. As a result, the particles in a liquid move faster in terms of vibration, rotation, and translation.
Can liquid have more energy than gas?Energy and State of Matter
A pure substance in the gaseous state contains more energy than in the liquid state, which in turn contains more energy than in the solid state. Particles has the highest kinetic energy when they are in the gaseous state.
Does gas have the most kinetic energy?According to the kinetic theory, particles of matter are in constant motion. The energy of motion is called kinetic energy. Particles of solids have the least kinetic energy and particles of gases have the most.
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Does liquid have more kinetic energy than gas
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