Heat Heat Calorimetry is the science of measuring the heat of chemical reactions or physical changes. Calorimetry involves the use of a calorimeter. ...more on Wikipedia about "Calorimetry"
The Carnot cycle is a particular thermodynamic cycle studied by Nicolas Léonard Sadi Carnot in the 1820s and expanded upon by Benoit Paul Émile Clapeyron in the 1830s and 40s. ...more on Wikipedia about "Carnot heat engine"
The coefficient of thermal expansion is used in two ways: ...more on Wikipedia about "Coefficient of thermal expansion"
A cooling curve is a line graph that represents the change of phase of matter, typically from either a gas to a solid or a liquid to a solid. Time is used in the x-axis while temperature is used for the y-axis. They are often used in chemistry and physics, and can apply (misleadingly) to matter behaviour during heating, as well as during cooling. ...more on Wikipedia about "Cooling curve"
The energy value of coal, or the fuel content, is the amount of potential energy in coal that can be converted into actual heating ability. The value can be calculated and compared with different grades of coal or even other materials. Materials of different grades will produce differing amounts of heat for a given mass. ...more on Wikipedia about "Energy value of coal"
Enthalpy (symbolized H, also called heat content) is the sum of the internal energy of matter and the product of its volume multiplied by the pressure. Enthalpy is a quantifiable state function, and the total enthalpy of a system cannot be measured directly; the enthalpy change of a system is measured instead. Enthalpy is a thermodynamic potential, and is useful particularly for nearly-constant pressure process, where any energy input to the system must go into internal energy or the mechanical work of expanding the system. The change in enthalpy of a system is nearly singularly meaningful for systems at constant pressure, when the change in enthalpy is equivalent to heat. Otherwise, there is no easily interpreted meaning for this state function. Thus, change in enthalpy can only properly be stated as heat of the reaction for reactions performed at constant pressure. For a simple system, with a constant number of particles, the difference in enthalpy is the maximum amount of thermal energy derivable from a thermodynamic process in which the pressure is held constant. ...more on Wikipedia about "Enthalpy"
Hand warmers are small (sometimes disposable) packets which are held in the hand and produce heat on demand to warm cold hands. ...more on Wikipedia about "Hand warmer"
Heat is a form of energy associated with the motion of atoms, molecules and other particles matter is composed of. It can be created by chemical reactions (such as burning,) nuclear reactions (such as fusion reactions taking place inside the Sun,) or electromagnetic dissipation (as in electric stoves.) Heat can be transferred between objects by radiation, conduction and convection. Temperature is used to indicate the level of elementary movement associated with heat. Heat can only be transferred between objects, or areas within an object, that have different temperatures. ...more on Wikipedia about "Heat"
A heat bath is a large system that is in thermal contact with some other system of interest. Large means here that the heat bath is unperturbed when in thermal contact with the system of interest. Thus the heat bath is effectively an infinite reservoir of energy and accessible quantum states at a given temperature. ...more on Wikipedia about "Heat bath"
Heat capacity (denoted as C) is a measurable physical quantity that characterizes the ability of a body to store heat. It is defined as the amount of heat needed at the given conditions and state of the body (foremost its temperature) to raise its temperature by one degree. Therefore, heat capacity is measured in units of joules per kelvin and is an extensive quantity. Dividing heat capacity by the body's mass yields a specific heat, which is an intensive quantity. ...more on Wikipedia about "Heat capacity"
The heat capacity ratio is simply the ratio of the heat capacity at constant pressure to that at constant volume ...more on Wikipedia about "Heat capacity ratio"
Heat conduction is the transmission of heat across matter. ...more on Wikipedia about "Heat conduction"
The heat death is a possible final state of the universe, in which it has "run down" to a state of no free energy to sustain motion or life. In physical terms, it has reached maximum entropy. ...more on Wikipedia about "Heat death of the universe"
In engineering and thermodynamics, a heat engine performs the conversion of heat energy to mechanical work by exploiting the temperature gradient between a hot " source" and a cold " sink". Heat is transferred to the sink from the source, and in this process some of the heat is converted into work. ...more on Wikipedia about "Heat engine"
The heat equation is an important partial differential equation which describes the variation of temperature in a given region over time. In the special case of heat propagation in an isotropic and homogeneous medium in the 3- dimensional space, this equation is ...more on Wikipedia about "Heat equation"
The Heat of combustion (ΔcH0) is the energy released as heat when a compound undergoes complete combustion with oxygen. The chemical reaction is typically a hydrocarbon reacting with oxygen to form carbon dioxide, water and heat. It may be expressed with the units; ...more on Wikipedia about "Heat of combustion"
The heat of sublimation is a thermodynamic property of substances at temperatures above their critical point, i.e., where the gas and liquid phases are not distinguishable. It is defined as the heat required to sublimate one mole of the substance at a given combination of temperature and pressure, usually standard temperature and pressure (STP). The heat of sublimation is usually expressed in kJ/mol, although the less custmary kJ/kg is also encountered. ...more on Wikipedia about "Heat of sublimation"
A heat pipe is a heat transfer mechanism that can transport large quantities of heat with a very small difference in temperature between the hot and cold interfaces. ...more on Wikipedia about "Heat pipe"
The heat transfer coefficient is used as a fudge factor in calculating heat transfer in thermodynamics. The heat transfer coefficent is often calculated from the Nusselt number (a dimensionless number). Below is an example where it is used to find the heat lost from a hot tube to the surrounding area. ...more on Wikipedia about "Heat transfer coefficient"
Heating value (or calorific value) is used to define the amount of heat released during the combustion of a fuel or food. It is measured in units of energy per amount of material. Depending on the context, heating values may be reported as Btu/m³, kcal/kg, kJ/kg, J/ mol, or a variety of other combinations of units. Heating value in commonly determined by use of a bomb calorimeter. ...more on Wikipedia about "Heating value"
The higher heating value (also known gross calorific value or gross energy) of a fuel is defined as the amount of heat released by a specified quantity (initially at 25°C) once it is combusted and the products have returned to a temperature of 25°C. ...more on Wikipedia about "Higher heating value"
Latent heat describes the amount of energy in the form of heat that is required for a material to undergo a change of phase (also known as "change of state"). Two latent heats are typically described. One is the latent heat of fusion ( melting), and the other is the latent heat of vaporization ( evaporation). ...more on Wikipedia about "Latent heat"
The radiation budget represents the balance between incoming energy from the Sun and outgoing thermal (longwave) and reflected (shortwave) energy from the Earth. The "budget" is an analogy between conservation of energy and household budgeting. ...more on Wikipedia about "Radiation budget"
When two pieces of ice are brought into contact under pressure, the ice melts at the plane of contact, and the water thus formed freezes when the pressure is relieved, thus uniting the two pieces of ice. Michael Faraday first called the phenomena regelation. ...more on Wikipedia about "Regelation"
Room temperature, in laboratory reports, is taken to be roughly 21–23 degrees Celsius (69-73 degrees Fahrenheit), or 294–296 kelvins. ...more on Wikipedia about "Room temperature"
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