enthalpy
Thermodynamic heat measure
Enthalpy is a measure of total energy in a thermodynamic system, combining internal energy with the energy required to make room for it under pressure.
Chemists and engineers use enthalpy to track heat flow in reactions and processes: The enthalpy change tells us whether the reaction releases or absorbs heat.
A negative enthalpy change means heat is released; positive means heat is absorbed.
Transferred thermal energy
- energyPower to do work
- entropyQuantified chaos in systems
- temperatureMeasured heat intensity
- pressureForce upon contact
volume · work · calorimetry · joules · kilojoules · thermal · isothermal · isobaric
Releasing energy as heat
- endothermicAbsorbing thermal energy
- activation energyMinimum energy for transformation
- bond energyStrength of atomic linkage
- catalystAgent enabling change
equilibrium · stoichiometry · yield · products · reactants · thermochemistry · calorimeter · bomb calorimeter
Conversion to gas
- fusionJoining into unity
- sublimationSolid to gas directly
- condensationVapor turning to liquid
- solidificationTransition to firm state
latent heat · boiling point · melting point · triple point · critical point · heat of fusion · saturation · superheating
Raising temperature artificially
- coolingLosing thermal energy
- refrigerationHeat removal for preservation
- air conditioningIndoor cooling system
- humidityMoisture in atmosphere
dew point · evaporator · condenser · compressor · refrigerant · heat pump · heat exchanger · BTU
Sharing electrons between atoms
- ionicConcerning charged particles
- hydrogen bondElectronegativity-based intermolecular attraction
- van der WaalsWeak intermolecular attractive force
- electronegativityAtomic electron attraction strength
bond strength · diatomic · polyatomic · atomization · solvation · hydration
heat
Transferred thermal energy
- energyPower to do work
- entropyQuantified chaos in systems
- temperatureMeasured heat intensity
pressure · volume · work · calorimetry · joules · kilojoules · thermal · isothermal · isobaric · specific heat
exothermic
Releasing energy as heat
- endothermicAbsorbing thermal energy
- activation energyMinimum energy for transformation
- bond energyStrength of atomic linkage
catalyst · equilibrium · stoichiometry · yield · products · reactants · thermochemistry · calorimeter · bomb calorimeter · spontaneous
vaporization
Conversion to gas
- fusionJoining into unity
- sublimationSolid to gas directly
- condensationVapor turning to liquid
solidification · latent heat · boiling point · melting point · triple point · critical point · heat of fusion · saturation · superheating · supercooling
heating
Raising temperature artificially
- coolingLosing thermal energy
- refrigerationHeat removal for preservation
- air conditioningIndoor cooling system
humidity · dew point · evaporator · condenser · compressor · refrigerant · heat pump · heat exchanger · BTU · tonnage
covalent
Sharing electrons between atoms
- ionicConcerning charged particles
- hydrogen bondElectronegativity-based intermolecular attraction
- van der WaalsWeak intermolecular attractive force
electronegativity · bond strength · diatomic · polyatomic · atomization · solvation · hydration
- energyelectricity, power, oil, fuel, gas
- heatheat transfer, thermal energy, heatwave, radiation, convection
- unitsunit, angstrom, yard, meter, base units
- chemistryatom, atoms, organic chemistry, molecule, chemistry
- Heat conceptsmelting, evaporation, conduction, convection, boiling
- Heat Scienceheat transfer, heat capacity, heat flow, specific heat, latent heat