Chemical Thermodynamics: Measurement of Internal energy change, δU and enthalpy, ΔH Heat capacity is the measurable physical quantity that characterizes the amount of heat required to change a substance’s temperature by a given amount Calorimeter is a device for measuring the heat produced during an electrical, mechanical or chemical reaction, and for calculating the heat … Read more
Chemical Thermodynamics: Heat capacity and Specific heat Heat capacity is the amount of heat(measured in Joules or Calories) required to raise a unit amount of substance (measured in grams or moles) the temperature of an object by 1°C temperature (measured in C or K). The heat capacity of an object is C≡Q/ΔT. This addition of … Read more
Chemical Thermodynamics: Internal energy and Enthalpy The total energy inside a system may change by two formats: either heat and/or work. However, some energy is already present within a system before transformation takes place. The internal energy of a system is defined as the sum of the kinetic and potential energies of the particles that … Read more
Chemical Thermodynamics: First law of thermodynamics The first law of thermodynamics is explained as “The total change in internal energy of a system is the sum of the heat added to it and the work done on it.”The conservation of energy take place which essentially means that “energy cannot be created or destroyed” or that … Read more
Chemical Thermodynamics: state functions The substance is usually encountered in one of the three main states: gaseous, liquid, or solid. Hence, under various conditions, the substance can exist in different states. In a fixed condition, the substance will always be in one and the same state. For instance, at atmospheric pressure and a temperature of … Read more
Chemical Thermodynamics: Intensive properties Intensive properties are independent of the amount of mass of a system and are a local physical property. Therefore, it is a bulk property. If a quantity of substance in a given state is divided into two parts with intensive and extensive properties, each part will have equal number of these … Read more
Ideal behavior The Ideal Gas law equation simply demonstrates the relationship between pressure, volume, and temperature for gases. These particular relationships originate from or are derived from Boyle’s Law, Charles’s Law, and Gay-Lussac’s Law. An ideal gas refers to a theoretical gas, which is composed of several random moving point particles, whose interactions are only … Read more
Deviation from ideal behavior Real gases’ behavior generally has an agreement with the ideal gas equation’s predictions within 5% on the normal pressures and temperatures. At high or low pressures, in real gases, you’ll see the significant deviation from ideal gas behavior. Johannes van der Waals, the Dutch physicist in 1873 was researching for a … Read more
The kinetic molecular theory describes the microscopic properties of atoms or molecules and their interactions that would further bring up macroscopic properties that include volume, pressure and temperature. This theory is important with a view to explaining the existence of substances in three different states (solid, liquid and gaseous). Also, it explains the behavior … Read more
It is quite certain that liquefaction of gases would be a star too far without considering the physical factors that include pressure, temperature and volume. The most appropriate factors for change in physical state of the element are termed as the critical factors. What is Critical Temperature? The critical temperature for a specific substance … Read more