Kinetic theory of gases grade 11 physics notes khullakitab. This is the first of five lectures on the kinetic theory of gases. Instructor so i wanna talk to you a little more about the kinetic molecular theory of gases. We can directly measure, or sense, the action of the gas. Ideal gasthe number of molecules is largethe average separation between molecules is largemolecules moves randomlymolecules obeys newtons lawmolecules collide elastically with each other. Class 11 chapter 9 behaviour of perfect gas kinetic theory. The kinetic theory of gases is valid for gases themselves, gaseous mixtures, and plasma. Reif ends with a much wider ranging discussion of kinetic theory, transport and stochastic processes. Molecules of diatomic gas are made up of two atoms joined rigidly. All the exercise of chapter 24 kinetic theory of gases questions with solutions to help you to revise complete syllabus and score more marks. This course contains video lectures which explaining concepts and knowledge of this subject. So the first four topics of the course thermodynamics, probability, this kinetic theory of gases, and basic of statistical physics.
It is the type of matter which has got fixed shape and volume. The molecules of a gas are identical spherical, rigid and perfectly elastic point masses. The model describes a gas as a large number of identical submicroscopic particles atoms or molecules, all of which are in constant, rapid, random motion. Revision notes on kinetic theory of gases askiitians. Collisions between molecules and with their container are perfectly elastic. What this basically says is that the macroscopic properties of a gas, like the pressure or the volume or the temperature are just a result of the microscopic. As we do not wish to introduce here the hypothesis of the kinetic theory, we. Daniel bernoulli, in 1738, was the first to understand air pressure from a molecular point of view.
We shall now see how this model can be expressed quantitatively in terms of the kinetic theory of gases. Air is a gas, and gases can be studied by considering the small scale action of individual molecules or by considering the large scale action of the gas as a whole. Every gas consists of extremely small particles known as molecules. The british scientist james clerk maxwell and the austrian physicist ludwig boltzmann, in the 19th century. A normal solution to the revised enskog kinetic theory of smooth monocomponent granular gases is obtained via the chapmanenskog method for states close to the local homogeneous cooling state. An ideal gas a gas that exactly follows the statements of the kinetic theory. The model, called the kinetic theory of gases, assumes that the molecules are very small relative to the distance between molecules. Kinetic theory of gases classroom lecture by pradeep kshetrapal.
Here t is the temperature in kelvin or absolute scale. Kinetic theory of gases, a theory based on a simplified molecular or particle description of a gas, from which many gross properties of the gas can be derived. The kinetic theory of gases introduction and summary previously the ideal gas law was discussed from an experimental point of view. Ideal gasthe number of molecules is largethe average separation between molecules is largemolecules moves randomlymolecules obeys newtons lawmolecules collide elastically with each other and with the wallconsists of identical molecules. The kinetic theory relates this energy to the temperature and pressure of a gas. This course is prepared and taught by pradeep kshetrapal sir. Kinetic theory simple english wikipedia, the free encyclopedia. Note 17 the kinetic theory of gases sections covered in the text. Xi125 kinetic theory of gases 2015 pradeep kshetrapal physics duration. Behaviour of perfect gases and kinetic theory of gases. The relationship between pressure, density, and temperature was later found to have a basis in an atomic or molecular model of gases called the kinetic theory of gases that was developed by maxwell in the. Molecule of monoatomic gas can move in any direction in space so it can have three independent motions and hence 3 degrees of freedom all translational 2 diatomic gas. We can directly measure, or sense, the large scale action of the gas.
Lectures on kinetic theory of gases and statistical physics. It allows us to understand the behavior of molecules in terms of macroscopic quantities by using averages. The ideal gas, real gases, distribution of velocities of gas molecules, collision properties of gas molecules, transport phenomena in gases. The kinetic theory of gases is a historically significant, but simple, model of the thermodynamic behavior of gases, with which many principal concepts of. Relate to the 1st law of thermodynamics thermal expansion cracking the nut. Chapman and cowling, the mathematical theory of nonuniform gases lifshitz and pitaevskii, physical kinetics both of these are old school. The kinetic theory of gases is a historically significant, but simple model of the thermodynamic behavior of gases with which many principal concepts of thermodynamics were established. The molecules are in constant, random motion and frequently collide with each other and with the walls of any container. Foundations of the hypothesis, pressure of gases, maxwells law, ideal and actual gases, molecular and atomic energy, molecular free paths, viscosity of gases, diffusin of gases and conduction of heat. Kinetic theory of gases this is a statistical treatment of the large ensemble of molecules that make up a gas. Molecules are, in a great numbers, everywhere and there is no vacuum at 100%. Boyle, newton and several others tried to explain the behaviour of gases by considering that gases are made up of tiny atomic.
Postulate 1 zgases consist of discrete molecules that are relatively far apart. Instead, pressure is caused by the molecules colliding with each other and their. L2a 2 current density in terms of velocity of charge. Our new crystalgraphics chart and diagram slides for powerpoint is a collection of over impressively designed datadriven chart and editable diagram s guaranteed to impress any audience. K is a constant for the given sample but varies with the volume of the gas. Gases are highly mobile compounds and therefore have a high kinetic energy. Derivation of expression for pressure of gas kinetic theory of gases part 2 duration. Pradeep fundamental physics for class 11 part i and part ii concept of. The molecules of a given gas are all identical but are different from those of another gas. According to this theory, gases are made up of tiny particles in random, straight line motion. Free kinetic theory books download ebooks online textbooks. Kinetic molecular theory of gases video khan academy. Apr 22, 2019 assumptions of kinetic theory of gases. Schekochihiny the rudolf peierls centre for theoretical physics.
We already saw the thermodynamic one as dq divided by t meaning ds. Many gases deviate slightly from agreeing perfectly with the kinetic theory of gases. This page contains revision notes on kinetic theory of gases. Think of it as what the ideal gas law would look like when viewed through a microscope. This site is like a library, use search box in the widget to get ebook that you want. Kinetic theory can be used to deduce some of the equilibrium properties of gases, but the methods of statistical thermodynamics are more powerful in that respect. Air inside a closed container is saturated with water vapour. A perfect gas at 270c is heated at constant pressure so as to double its volume. The molecular kinetic theory of gases the properties of a prefect ideal gas can be rationalized qualitatively in terms of a model in which the molecules of the gas are in continuous chaotic motion. As an example, the number density n of a gas at room temperature t and one. Kinetic theory of gases download ebook pdf, epub, tuebl.
Ppt kinetic theory of gases powerpoint presentation. Kinetic theory or kinetic theory of gases attempts to explain overall properties of gases, such as pressure, temperature, or volume, by considering their molecular composition and motion. Gases can be studied by considering the small scale action of individual molecules or by considering the large scale action of the gas as a whole. We use the kinetic theory of gases to peer through the galaxy of the ideal gas law to look at the stars within. Ideal gas law and kinetic theory of gases chapter 20 entropy and the second law of thermodynamics now we to look at temperature, pressure, and internal energy in terms of the motion of molecules and atoms. Instead of considering gases on a macroscopic scale yknow, people sized, it treats gases as a collection of millions of molecules. In each one of them, you will define some version of entropy. Jun 12, 2014 but to study the action of the molecules, we must use a theoretical model. Xi1012 kinetic theory 1 2014pradeep kshetrapal physics. Basically, this kinetic theory allowed properties of gases at low pressures to be predicted, and it allowed an understanding of why some of the. The aim of kinetic theory is to account for the properties of gases in terms of the forces between the molecules, assuming that their motions are described by the laws of mechanics usually classical newtonian mechanics, although quantum mechanics is needed in some cases. The aim of kinetic theory is to account for the properties of gases in terms of the forces between the molecules, assuming that their motions are described by the laws of mechanics usually classical newtonian. Note 17 the kinetic theory of gases university of toronto. The time rate of flow of charge through any crosssection is called current.
Free pdf download of hc verma solutions for class 12 physics part2 chapter 24 kinetic theory of gases solved by expert physics teachers on. Here we see how the temperature and pressure of a gas arises from the average movement of its constituent atoms and molecules. Kinetic theory of gases kinetic interpretation of temperature. The increase in temperature of the gas will be 0a 600 c b 3270c c 540c d3000c 2. So the gas is characterised by the following properties. The kinetic theory of gases is concerned with molecules in motion and with the microscopic and macroscopic consequences of such motion in a gas. Xi125 kinetic theory of gases 2015pradeep kshetrapal.
A gas is a simpler system than either a liquid or a solid. Kinetic theory of gases everything up to this point has been empirical there is clearly a great deal of truth in the equations however, there is no physical picture to gain insight, one must develop and validate models we look at a molecular kinetic theory of gases model to begin that process. The assumptions of the kinetic theory of gases are a gas consists of a large number of molecules in rapid, random motion. Kinetic theory of gases part1, classroom lecture by pradeep kshetrapal. The kinetic theory of gases also known as kinetic molecular theory is a law that explains the behavior of a hypothetical ideal gas. May 08, 2018 kinetic theory of gases kinetic interpretation of temperature. The theory basically states that pressure is not caused by molecules pushing each other away, like earlier scientists thought.
Lecture 14 ideal gas law and terms of the motion of molecules. The kinetic theory of gases also known as kineticmolecular theory is a law that explains the behavior of a hypothetical ideal gas. Schekochihiny the rudolf peierls centre for theoretical physics, university of oxford, oxford ox1 3np, uk. Pradeep kshetrapal current electricity 5 v a electric current. In case of uniform flow of charge through a crosssection normal to it as. And that is exactly what we are going to take a look at here, this kinetic theory. Hc verma class 12 physics part2 solutions for chapter 24. The kinetic theory of gases describes a gas as a large number of submicroscopic particles atoms or molecules, all of which are in constant, rapid, random motion. In gases the intermolecular forces are very weak and its molecule may fly apart in all directions. The foundations of the kinetic theory of gases were formulated by l. Rms velocity, maxwells distribution of velocities and mean free path duration. Pradeep kshetrapal current electricity genius physics. The randomness arises from the particles many collisions with each other and with the walls of the container.
The various properties of a gas can be accounted for that is, can be calculated using this molecular model. Kinetic theory of gases is a branch of statistical mechanics. The kinetic theory of gases is a model in which molecules move freely with kinetic energy. The force of attraction between any two molecules of a solid is very large. The kineticmolecular theory the basic assumptions of kineticmolecular theory are.
So if through a crosssection, q charge passes in time t then t q i av and instantaneous current dt dq t q ilim t u u u 0. The british scientist james clerk maxwell and the austrian physicist ludwig boltzmann, in the 19th century, led in establishing the. Kinetic theory of gases article about kinetic theory of. The relationship between pressure, density, and temperature was later found to have a basis in an atomic or molecular model of gases called the kinetic theory of gases that was developed by maxwell in the late 1800s. What this basically says is that the macroscopic properties of a gas, like the pressure or the volume or the temperature are just a result of the microscopic properties of the gas molecules, like the position and the speeds of these molecules.
Xi125 kinetic theory of gases 2015pradeep kshetrapal physics. It turns out that also we will encounter in cases later on, where rather than having a discrete probability, we have a probability density function. Instructor so i wanna talk to you a little more about the kineticmolecular theory of gases. Chart and diagram slides for powerpoint beautifully designed chart and diagram s for powerpoint with visually stunning graphics and animation effects. Lecture 14 ideal gas law and terms of the motion of. Click download or read online button to get kinetic theory of gases book now. Thus the kinetic theory describes the pressure of an ideal gas using a classical description of the motion of a single.
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