# Thermodynamics

## Effects of work, heat and energy on systems

### 1st Law of Thermodynamics

The First Law of Thermodynamics simply states that energy can be neither created nor destroyed (conservation of energy). Thus power generation processes and energy sources actually involve conversion of energy from one form to another, rather than creation of energy from nothing

### 2nd Law of Thermodynamics

The second law is concerned with entropy, which is a measure of disorder. The second law says that the entropy of the universe increases

### Absorbed Solar Radiation

Solar radiation absorbed by various materials

### Acetone - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of acetone at temperatures ranging from -95 to 275 °C (-138 to 530 °F) at atmospheric and higher pressure - Imperial and SI Units

### Acetone - Thermophysical Properties

Chemical, physical and thermal properties of acetone, also called 2-propanone, dimethyl ketone and pyroacetic acid. Phase diagram included.

### Alternative Fuels - Properties

Properties of alternative fuels like Biodiesel, E85, CNG and more

### Aluminum - Radiation Heat Emissivity

Radiation heat emissivity of unoxidized, oxidized and polished aluminum

### Ammonia - Density at Varying Temperature and Pressure

Online calculator, figures and tables showing density and specific weight of ammonia at temperatures ranging -50 to 425 °C (-50 to 800 °F) at atmospheric and higher pressure - Imperial and SI Units

### Ammonia - Dynamic and Kinematic Viscosity

Online calculator, figures and tables showing dynamic (absolute) and kinematic viscosity of gasous and liquid ammonia at temperatures ranging from -73 to 425°C (-100 to 800°F) at pressure ranging from 1 to 1000 bara (14.5 - 14500 psia) - SI and Imperial Units

### Ammonia - Prandtl Number

Figures and table showing changes in Prandtl number for ammonia with changes in temperature and pressure

### Ammonia - Properties at Gas-Liquid Equilibrium Conditions

Figures and tables showing how the properties of liquid and gaseous ammonia changes along the boiling/condensation curve (temperature and pressure between triple point and critical point conditions). An ammonia phase diagram are included.

### Ammonia - Specific heat (heat capacity) at varying temperature and pressure

Online calculator, figures and tables showing specific heat (heat capacity), C_{P} and C_{V}, of gasous and liquid ammonia at temperatures ranging from -73 to 425°C (-100 to 800°F) at pressure ranging from 1 to 100 bara (14.5 - 1450 psia) - SI and Imperial Units

### Ammonia - Thermal Conductivity at Varying Temperature and Pressure

Online calculator, figures and tables showing thermal conductivity of liquid and gaseous ammonia at temperatures ranging -70 to 425 °C (-100 to 800 °F) at atmospheric and higher pressure - Imperial and SI Units

### Ammonia - Thermophysical Properties

Chemical, Physical and Thermal Properties of Ammonia. Phase diagram included.

### Ammonia - Vapour Pressure at gas-liquid equilibrium

Figures and table showing ammonia saturation pressure at boiling point, SI and Imperial units

### Argon - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of argon, Ar, at varying temperature and pressure - Imperial and SI Units

### Arithmetic and Logarithmic Mean Temperature Differences in Heat Exchangers

Arithmetic Mean Temperature Difference - *AMTD* - and Logarithmic Mean Temperature Difference - *LMTD* - formulas with examples - Online Mean Temperature Calculator

### Benzene - Density and Specific Weight

Online calculator, figures and table showing density and specific weight of benzene, C_{6}H_{6}, at temperatures ranging from 5 to 325 °C (42 to 620 °F) at atmospheric and higher pressure - Imperial and SI Units

### Benzene - Dynamic and Kinematic Viscosity

Online calculator, figures and table showing dynamic and kinematic viscosity of benzene, C_{6}H_{6}, at varying temperature and pressure - Imperial and SI Units

### Benzene - Thermophysical properties

Chemical, physical and thermal properties of benzene, also called benzol. Phase diagram included.

### Bimetallic Strips

Heat and bending of bimetallic strips

### Butane - Density and Specific Weight

Online calculators, figures and tables showing density and specific weight of liquid and gaseous butane, C_{4}H_{10}, at varying temperarure and pressure, SI and Imperial units

### Butane - Dynamic and Kinematic Viscosity

Online calculators, figures and tables showing dynamic and kinematic viscosity of liquid and gaseous butane, C_{4}H_{10}, at varying temperarure and pressure, SI and Imperial units

### Butane - Specific Heat (Heat Capacity)

Online calculators, figures and tables showing specific heat (heat capacity), Cp and Cv, of gasous and liquid butane, C_{4}H_{10}, at varying temperarure and pressure, SI and Imperial units

### Butane - Thermal Conductivity

Online calculators, figures and tables showing thermal conductivity of liquid and gaseous butane, C_{4}H_{10}, at varying temperarure and pressure, SI and Imperial units

### Carbon dioxide - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of carbon dioxide, CO_{2}, at temperatures ranging from -50 to 775 °C (-50 to 1400 °F) at atmospheric and higher pressure - Imperial and SI Units

### Carbon Dioxide - Dynamic and Kinematic Viscosity

Online calculator, figures and table showing dynamic and kinematic viscosity of carbon dioxide, CO_{2}, at varying temperature and pressure - Imperial and SI Units

### Carbon dioxide - Prandtl Number

Figures and table showing changes in Prandtl number for carbon dioxide with changes in temperature and pressure

### Carbon dioxide - Thermal Conductivity

Online calculator, figures and table showing thermal conductivity of carbon dioxide, CO_{2}, at temperatures ranging from -50 to 775 °C (-50 to 1400 °F) at atmospheric and higher pressure - Imperial and SI Units

### Carbon Dioxide - Thermophysical Properties

Chemical, physical and thermal properties of carbon dioxide. Phase diagram included.

### Carbon Monoxide - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of carbon monoxide, CO, at varying temperature and pressure - Imperial and SI Units

### Carnot Efficiency

The efficiency of the Carnot cycle

### Coefficients of Linear Thermal Expansion

Linear temperature expansion coefficients for aluminum, copper, glass, iron and other common materials

### Conductive Heat Transfer

Heat transfer takes place as conduction in a soilid if there is a temperature gradient

### Convective Heat Transfer

Heat transfer between a solid and a moving fluid is called convection. This is a short tutorial about convective heat transfer

### Cooling Mode - Heat Flux

Heat fluxes for various cooling or heat transfer modes

### Critical Points of some Substances

Critical points of some common substances like air, argon, helium and more

### Critical Temperatures and Pressures for some Common Substances

Critical temperatures and pressures for some common substances - air, alcohol, ether, oxygen and more

### Density of Liquids versus change in Pressure and Temperature

Density and specific volume of a liquid versus change in pressure and temperature

### Diffusion Coefficients of Gases in Water

Diffusion flux [kg/m^{2}s] tells how fast a substanse solved in another substance flows due to concentration gradients. Diffusion constants [m^{2}/s] are given for several gases in water

### Dowtherm A

Physical properties of Dowtherm A

### Efficiency

Efficiency is the ratio between the useful energy output and the energy input

### Emissivity Coefficients for some common Materials

Radiation emissivities of some common materials like water, ice, snow, grass and more

### Emissivity Coefficients Materials

The radiation heat transfer emissivity coefficient of some common materials as aluminum, brass, glass and many more

### Energy

Energy is the capacity to do work

### Energy Conversion Factors

Convert between energy units

### Energy Storage Density

Energy density - by weight and volume - for some ways to store energy

### Energy Storage in Heated Water - kWh

Thermal energy stored in heated water

### Energy Transfer Equation

Fluid energy transfer

### Ethane - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of ethane, C_{2}H_{6}, at varying temperature and pressure - Imperial and SI Units

### Ethane - Thermal Conductivity

Online calculator, figures and table showing thermal conductivity of ethane, C_{2}H_{6}, at varying temperature and pressure - Imperial and SI Units

### Ethanol - Dynamic and Kinematic Viscosity

Online calculator, figures and tables showing dynamic and kinematic viscosity of ethanol, C_{2}H_{5}OH, at varying temperature and pressure - Imperial and SI Units

### Ethanol - Specific Heat (Heat Capacity), C_{p} and C_{v}

Online calculators, figures and tables showing specific heat (heat capacity), Cp and Cv, of gasous and liquid ethanol at temperatures ranging from -25 to 325 °C (-10 to 620 °F) at atmospheric and higher pressure - Imperial and SI Units

### Ethanol - Thermophysical properties

Chemical, physical and thermal properties of ethanol (also called alcohol or ethyl alcohol). Phase diagram included.

### Ethylene - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of ethylene, C_{2}H_{4}, at varying temperature and pressure - Imperial and SI Units

### Ethylene - Dynamic and Kinematic Viscosity

Online calculator, figures and tables showing dynamic and kinematic viscosity of ethylene, C_{2}H_{4}, also called ethene or acetene, at varying temperature and pressure - Imperial and SI Units

### Ethylene - Thermal Conductivity

Online calculator, figures and table showing thermal conductivity of ethylene, also called ethene or acetene, C_{2}H_{4}, at varying temperature and pressure - Imperial and SI Units

### Ethylene - Thermophysical Properties

Chemical, physical and thermal properties of ethylene, also called ethene, acetene and olefiant gas. Phase diagram included.

### Fouling and Reduced Heat Transfer in Heat Exchangers

The heat-transfer in a heat exchanger is reduced by fouling

### Freezing and Melting Points for common Liquids

Common fluids and their freezing and melting points

### Freezing Mixtures and Cooling Agents

Freezing mixtures, cooling agents and freezing points

### Heat Capacity

The heat capacity of a substance is the amount of heat required to change its temperature by one degree, and has units of energy per degree

### Heat Exchanger Heat Transfer Coefficients

Overall heat transfer coefficients in heat exchanger constructions - tubular, plate or spiral

### Heat of combustion

Tabulated values of heat of combustion (= energy content) of common substances, together with examples showing how to calculate the heat of combustion

### Heat Value

The gross (high) and net (low) heating values

### Heat, Work and Energy

Heat, work and energy tutorial - essentials as specific heat

### Heating Up Applications - Energy Required and Heat Transfer Rates

Energy required when heating up substances

### Heavy Water - Thermophysical Properties

Thermodynamic properties of heavy water (D_{2}O) - density, melting temperature, boiling temperature, latent heat of fusion, latent heat of evaporation, critical temperature and more

### Helium - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of helium, He, at varying temperature and pressure - Imperial and SI Units

### Hydrogen - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of hydrogen, H_{2}, at temperatures ranging from -260 to 325 °C (-435 to 620 °F) at atmospheric and higher pressure - Imperial and SI Units

### Hydrogen - Thermal Conductivity

Online calculator, figures and table showing thermal conductivity of hydrogen, H_{2}, at varying temperature and pressure - Imperial and SI Units

### Hydrogen sulfide - Thermophysical Properties

Chemical, physical and thermal properties of hydrogen sulfide, H_{2}S, also called hydrosulfuric acid, sewer gas and stink damp. Phase diagram included.

### Latent Heat of Melting for some common Materials

Latent heat of fusion when changing between solid or liquid state for common materials like aluminum, ammonia, glycerin, water and more

### Linear Thermal Expansion

Linear temperature expansion - online calculator

### Liquid ammonia - Thermal Properties at saturation pressure

Density, specific heat, thermal conductivity, viscosity and Prandtls no. of liquid ammonia at its saturation pressure

### Methane - Dynamic and Kinematic Viscosity

Online calculator, figures and tables showing dynamic and kinematic viscosity of methane, CH_{4}, at varying temperature and pressure - Imperial and SI Units

### Methane - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of methane, CH_{4}, at temperatures ranging from -160 to 725 °C (-260 to 1300 °F) at atmospheric and higher pressure - Imperial and SI Units

### Methane - Prandtl number

Figures and table showing changes in Prandtl number for methane with changes in temperature and pressure

### Methane - Thermal Conductivity

Online calculator, figures and table showing thermal conductivity of methane, CH_{4}, at temperatures ranging from -160 to 725 °C (-260 to 1300 °F) at atmospheric and higher pressure - Imperial and SI Units

### Methane - Thermophysical Properties

Chemical, Physical and Thermal Properties of Methane - *CH _{4}*. Phase diagram included.

### Methanol - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of methanol,CH_{3}OH, at varying temperature and pressure - Imperial and SI Units

### Methanol - Dynamic and Kinematic Viscosity

Online calculator, figures and tables showing dynamic and kinematic viscosity of liquid methanol,CH_{3}OH, at varying temperature - Imperial and SI Units

### Methanol - Specific Heat (Heat Capacity)

Online calculator, figures and tables showing isobaric and isochoric heat capacity (specific heat) of methanol, CH_{3}OH, at varying temperature - Imperial and SI Units

### Methanol - Thermophysical Properties

Chemical, physical and thermal properties of methanol, CH_{3}OH (also called carbinol, wood alcohol, hydroxy methyl and methyl alcohol). Phase diagram included.

### Microwave Heating

Heating with microwaves

### Mixing Liquids and/or Solids - Final Temperatures

Calculate the final temperature when liquids or solids are mixed

### Mollier Chart for Water - Imperial Units

Mollier chart for water in English Units

### Mollier Chart for Water - Metric Units

Mollier chart for water in Metric Units

### Mollier Diagram for Water-Steam

Enthalpy-entropy diagram for water and steam

### Nitrogen - Enthalpy, Internal Energy and Entropy

Enthalpy, internal energy and entropy of Nitrogen as ideal gas

### Nitrogen - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of nitrogen, N_{2}, at temperatures ranging from -175 to 1325 °C (-280 to 2400 °F) at atmospheric and higher pressure - Imperial and SI Units

### Nitrogen - Dynamic and Kinematic Viscosity

Online calculator, figures and tables showing dynamic and kinematic viscosity of nitrogen, N_{2}, at varying temperature and pressure - Imperial and SI Units

### Nitrogen - Prandtl number

Figures and tables showing Prandtl number of nitrogen at varying temperarure and pressure, SI and Imperial units

### Nitrogen - Thermal Conductivity

Online calculator, figures and tables showing thermal conductivity of nitrogen, N_{2}, at varying temperarure and pressure, SI and Imperial units

### Nitrogen - Thermal Diffusivity

Figures and tables showing thermal diffusivity of nitrogen at varying temperarure and pressure, SI and Imperial units

### Nitrogen - Thermophysical Properties

Chemical, Physical and Thermal Properties of Nitrogen - *N _{2}*

### Overall Heat Transfer Coefficient

Calculate overall heat transfer coefficients for walls or heat exchangers

### Overall Heat Transfer Coefficients for Fluids - Heat Exchanger Surface Combinations

Average overall heat transmission coefficients for some common fluids and surface combinations as Water to Air, Water to Water, Air to Air, Steam to Water and more

### Oxygen - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of oxygen, O_{2}, at varying temperature and pressure - Imperial and SI Units

### Oxygen - Dynamic and Kinematic Viscosity

Online calculator, figures and tables showing dynamic and kinematic viscosity of oxygen, O_{2}, at varying temperature and pressure - Imperial and SI Units

### Pentane - Density and Specific Weight

Online calculator, figures and table showing density and specific weight of pentane, C_{5}H_{12}, at temperatures ranging from -130 to 325 °C (-200 to 620 °F) at atmospheric and higher pressure - Imperial and SI Units

### Pentane - Thermophysical Properties

Chemical, physical and thermal properties of pentane, also called n-pentane. Phase diagram included.

### Power Plant Performance Efficiency

Power plant heat rate, thermal efficiency, capacity factor, load factor, economic efficiency, operational efficiency, energy efficiency

### Propane - Density and Specific Weight

Online calculator, figures and tables showing density and specific weight of propane, C_{3}H_{8}, at temperatures ranging from -187 to 725 °C (-305 to 1300 °F) at atmospheric and higher pressure - Imperial and SI Units

### Propane - Dynamic and Kinematic Viscosity

Online calculators, figures and tables showing dynamic and kinematic viscosity of liquid and gaseous propane at varying temperarure and pressure, SI and Imperial units

### Propane - Prandtl Number

Figures and tables showing Prandtl Number of liquid and gaseous propane at varying temperarure and pressure, SI and Imperial units

### Propane - Specific Heat (Heat Capacity)

Online calculators, figures and tables showing specific heat (heat capacity), Cp and Cv, of gasous and liquid propane, C_{3}H_{8}, at varying temperature and pressure - Imperial and SI Units

### Propane - Thermal Conductivity

Online calculator, figures and tables showing thermal conductivity of liquid and gaseous propane at varying temperarure and pressure, SI and Imperial units

### Propane - Thermal Diffusivity

Figures and tables showing thermal diffusivity of liquid and gaseous propane at varying temperarure and pressure, SI and Imperial units

### Properties and State

Concept of properties and state

### Radiation Constants Building Materials

The radiation constant is the product between the Stefan-Boltzmann constant and the emissivity constant for a material

### Radiation Heat Transfer

Heat transfer due to emission of electromagnetic waves is known as thermal radiation

### Rankine Efficiency

The efficiency of the Rankine cycle

### Salt Hydrates - Melting points and Latent Energy

Melting points and latent energy of salt hydrates

### Solids - Volume Temperature Expansion Coefficients

Cubical expansion coefficients for solids

### Specific Heat - Online Unit Converter

Online specific heat converter with the most commonly used units

### Specific Heat and Individual Gas Constant of Gases

Specific heat at constant volume, specific heat at constant pressure, specific heat ratio and individual gas constant - *R* - common gases as argon, air, ether, nitrogen and many more ..

### Specific Heat of common Substances

Specific heat of materials like wet mud, granite, sandy clay, quartz sand and more

### Specific Heat of Food and Foodstuff

Specific heat of common food and foodstuff like apples, bass, beef, pork and many more

### Specific Heat of Liquids and Fluids

Common liquids and fluids - acetone, oil, paraffin, water and many more - and their specific heats

### Specific Heat of Solids

Common solids - like brick, cement, glass and many more - and their specific heats - in Imperial and SI units

### Specific Heats for Metals

Commonly used metals - aluminum, iron, mercury and many more - and their specific heats - imperial and SI units

### Standard enthalpy of formation, Gibbs energy of formation, entropy and molar heat capacity of organic substances

The standard enthalpy of formation, Gibbs energy of formation, entropy and molar heat capacity are tabulated for more than hundred organic substances.

### Standard state and enthalpy of formation, Gibbs free energy of formation, entropy and heat capacity

Definition and explanation of the terms standard state and standard enthalpy of formation, with listing of values for standard enthalpy and Gibbs free energy of formation, as well as standard entropy and molar heat capacity, of 370 inorganic compounds

### Standardized Enthalpies and Entropies

Standardized enthalpies and entropies for some common substances

### Storing Thermal Heat in Materials

Energy stored as sensible heat in materials

### Surface - Radiation Absorptivity

Radiation surface absorptivity

### Symbols Used to Denote a Chemical Reaction, Process or Condition

Explanation of symbols used as subscripts or superscripts to tell more about the type of chemical reaction, process or condition

### Temperature

Introduction to temperature - including Celsius, Fahrenheit, Kelvin and Rankine definitions - an online temperature converter

### Temperature Expansion Coefficients of Piping Materials

Expansion coefficients for common materials used in pipes and tubes - aluminum, carbon steel, cast iron, PVC, HDPE and more

### Thermal Conductivities for some common Liquids

Some fluids and their thermal conductivities

### Thermal Conductivities of Heat Exchanger Materials

Typical heat exchanger materials and their thermal conductivities

### Thermal Conductivity Conversion Factors

Convert between thermal conductivity units

### Thermal Conductivity of common Materials and Gases

Thermal conductivity of gases, insulation products, aluminum, asphalt, brass, copper, steel and other common materials

### Thermal Conductivity Online Converter

Convert thermal conductivities

### Thermal Expansion - Superficial i.e. Area

Superficial i.e area temperature expansion - online calculator

### Thermal Resistivity and Conductivity

Thermal resistivity and conductivity

### Thermal Transmittance and Thermal Resistance

Thermal transmittance U and thermal resistance R

### Thermodynamic Terms, Functions and Relations

Common thermodynamic terms and functions - potential energy, kinetic energy, thermal or internal energy, chemical energy, nuclear energy and more

### Thermodynamics key values internationally agreed

Internationally agreed, internally consistent, values for the thermodynamic properties (standard enthalpy of formation, entropy and [H°(298)-H°(0)]) of key chemical substances

### Third Law of Thermodynamics

The entropy of a substance is zero if the absolute temperature is zero

### Toluene - Density and Specific Weight

Linear temperature expansion coefficients for aluminum, copper, glass, iron and other common materials

### Toluene - Thermophysical Properties

Chemical, physical and thermal properties of toluene, also called methylbenzene, toluol and phenylmethane. Phase diagram included.

### Units of Heat - *BTU, Calorie and Joule*

The most common units of heat are *BTU - British Thermal Unit, Calorie and Joule*

### Volumetric - or Cubic Thermal Expansion

Volumetric temperature expansion with online calculator

### Volumetric or Cubical Expansion Coefficients of Liquids

Volumetric expansion coefficients of some common liquids

### WABT - weighted average bed temperature

Definition and examples of calculation of weighted average bed temperature in adiabatic reactors

### Water - Boiling Points at High Pressure

Online calculator, figures and tables showing boiling points of water at pressures ranging from 14.7 to 3200 psia (1 to 220 bara). Temperature given as °C, °F, K and °R.

### Water - Boiling Points at Vacuum Pressure

Online calculator, figures and tables giving the boiling temperatures of water in varying vacuum, SI and Imperial units.

### Water - Enthalpy (H) and Entropy (S)

Figures and tables showing the enthalpy and entropy of liquid water as function of temperature - SI and Imperial Units

### Water - Heat Capacity (Specific Heat)

Online calculator, figures and tables showing specific heat of liquid water at constant volume or constant pressure at temperatures from 0 to 360 °C (32-700 °F) - SI and Imperial units

### Water - Heat of Vaporization

Online calculator, figures and tables showing heat of vaporization of water, at temperatures from 0 - 370 °C (32 - 700 °F) - SI and Imperial units

### Water - Ionization Constant, pK_{w}, of normal and heavy water

Ionization constant (= dissociation constant = self-ionization constant = ion product = autoprotolysis constant ) of water and heavy water, given as function of temperature (°C and °F) in figures and tables

### Water - Melting Points at High Pressure

Online calculator, figures and tables showing melting points of water at pressures ranging from 0 to 29000 psia (0 to 2000 bara). Temperature given as °C, °F, K and °R.

### Water - Prandtl Number

Figures and tables showing Prandtl Number of liquid and gaseous water at varying temperarure and pressure, SI and Imperial units

### Water - Properties at Gas-Liquid Equilibrium Conditions

Figures and tables showing how the properties of water changes along the boiling/condensation curve (vapor pressure, density, viscosity, thermal conductivity, specific heat, Prandtl number, thermal diffusivity, entropy and enthalpy).

### Water - Specific Gravity

Figures and tables showing specific gravity of liquid water in the range of 32 to 700 °F or 0 to 370°C, using water density at four different temperatures as reference

### Water - Thermal Conductivity

Figures and tables showing thermal conductivity of water (liquid and gas phase) with varying temperature and pressure, SI and Imperial units

### Water - Thermal Diffusivity

Figures and tables showing thermal diffusivity of liquid and gaseous water at varying temperarure and pressure, SI and Imperial units

### Water Steam - the Critical Point and the Triple Point

Critical point is where vapor and liquid are indistinguishable and triple point is where ice, water and vapor coexist in thermodynamic equilibrium

### Work done by a Force

Work done by force acting on an object

### Zeroth Law of Temperature

Temperature and heat flow