Physical Chemistry

– In this topic, we will talk about Deduction of Gas laws from the Kinetic Gas Equation. Assumptions of the Kinetic Molecular Theory (1) A gas consists of extremely small discrete particles called molecules dispersed throughout the container. – The actual volume of the molecules is negligible compared to the …

– In this topic, we will talk about Derivation of the Kinetic Gas Equation. Derivation of the Kinetic Gas Equation – Starting from the postulates of the kinetic molecular theory of gases we can develop an important equation. – This equation expresses PV of a gas in terms of the …

Zeroth law of thermodynamics – The zeroth law of thermodynamics is a generalized statement about bodies in contact at thermal equilibrium and is the basis for the concept of temperature. – The most common definition of the zeroth law of thermodynamics is: If two thermodynamic systems are in thermal equilibrium …

– In this topic, we will discuss The Chemical Potential and Variation of Chemical Potential with Temperature and Pressure. Partial Molar Properties – We have so far studied the thermodynamic systems in which there was a change in thermodynamic properties with the variation of one or more state variables. – …

– In general, it may be stated that each substance in a given state has a tendency to escape from that state and this escaping tendency denoted by f is called fugacity. Fugacity and Activity – It has already been pointed out that equation ΔG = RT loge P2/P1 is applicable …

Van’t Hoff isotherm – The van’t Hoff isotherm gives the net work that can be obtained from a gaseous reactant at constant temperature when both the reactants and the products are at suitable arbitrary pressures. – It can be derived by using the “equilibrium box” which is a theoretical device …

– In this topic, we will discuss Clausius-Clapeyron equation – Derivation with Applications. The Clapeyron equation – A useful thermodynamic relation which gives us important information about a system  onsisting of any two phases of a single substance in chemical equilibrium is the Clapeyron equation. – It is derived from …

Gibbs Helmholtz Equations – These are two equations derived by J.W. Gibbs and H.Von Helmholtz and are known as Gibbs Helmholtz equations. – One equation can be expressed in terms of changes in free energy (ΔG) and enthalpy (ΔH), while the other can be expressed in terms of changes in …

– In this topic, we will discuss The Carnot Cycle : Definition, Theorem, Efficiency, Derivation and Sovled problems. The Carnot cycle – In 1824 Sadi Carnot proposed a theoretical heat engine to show that the efficiency was based upon the temperatures between which it operated. – Carnot’s imaginary engine could …

Definition of entropy – Entropy is a thermodynamic state quantity that is a measure of the randomness or disorder of the molecules of the system. – The symbol of entropy is S, while the change in disorder accompanying a process from start to completion is represented by ΔS.  – The entropy …

– In this topic, we will discuss the Macromolecules : Definition and Molecular Weight What are Macromolecules? – Colloidal solutions are formed by aggregation of atoms or molecules to give particles of colloidal size. – Macromolecules are substances which are themselves composed of giant molecules and dissolve in a solvent …

Second Law of Thermodynamics: MCQ Quiz with answers – In this subject, you will find 49 questions and answers MCQ on The Second Law of Thermodynamics. 1. A process which proceeds of its own accord, without any outside assistance, is called  ____ . (a) non-spontaneous process (b) spontaneous process (c) …

– In this topic, we will discuss The Applications of Colloids. Applications of Colloids – Colloids play an important role in our daily life and industry. – A knowledge of colloid chemistry is essential to understand some of the various natural phenomena around us. – Colloids make up some of …

– In this topic, we will discuss The Gels : Defination, Types, and Properties. What are Gels? – A gel is a jelly-like colloidal system in which a liquid is dispersed in a solid medium. – For example, when a warm sol of gelatin is cooled, it sets to a …

Defination of Emulsions – Emulsions are liquid-liquid colloidal systems. – In other words, an emulsion may be defined as a dispersion of finely divided liquid droplets in another liquid. – Generally one of the two liquids is water and the other, which is immiscible with water, is designated as oil. …

– In this subject, we will discuss the Associated Colloids. Associated Colloids – The molecules of substances as soaps and artificial detergents are smaller than the colloidal particles. However in concentrated solutions these molecules form aggregates of colloidal size. – Substances whose molecules aggregate spontaneously in a given solvent to …

Electrical Properties of Sols – In this topic we will discuss the Electrical Properties of Sols as follow: (1) The sol particles carry an electric charge. (2) Electrophoresis. (3) Electro-osmosis. (4) Coagulation or Precipitation. (5) Protective action of sols. (6) Origin of charge on sol particles. (1) The sol particles …

Kinetic Properties of Sols – In this topic, we will discuss Kinetic Properties of Sols. Brownian Movement – When a sol is examined with an ultramicroscope, the suspended particles are seen as shining specks of light. – By following an individual particle it is observed that the particle is undergoing …

Optical Properties of Sols – In this topic, we will discuss Optical Properties of Sols as follow: Sols exhibit Tyndall effect Ultramicroscope shows up the presence of individual particles Sol particles can be seen with an Electron microscope (1) Sols exhibit Tyndall effect – When a strong beam of light …

– In this topic, we will discuss Preparation of Sols, Purification of Sols and its colors Preparation of Sols – Lyophilic sols may be prepared by simply warming the solid with the liquid dispersion medium e.g., starch with water. – On the other hand, lyophobic sols have to be prepared …