Thermochemistry Flashcards

Flashcards about Thermochemistry

Thermochemistry

The part of chemistry that studies the amount of heat (energy) involved in chemical reactions.

Thermochemistry

The study of the heat involved in chemical reactions.

Temperature

The measure of the degree of agitation of the particles that constitute a substance.

Heat

Thermal energy in transit, which goes from one body to another due to the temperature difference, always going from the hotter body to the colder one.

Exothermic Reactions

Reactions that release heat.

Endothermic Reactions

Reactions that absorb heat.

Exothermic Processes

Burning candles, combustion of alcohol or petroleum derivatives, propane burning, liquefaction or condensation of water.

Endothermic Processes

Water boiling, water fusion (ice melting), photosynthesis, instant ice pack.

Exothermic Processes Formula

AH = Hp - HR, AH < 0

Endothermic Processes Formula

AH = Hp - HR, AH > 0

ΔH = +

Endothermic, example: fusion, vaporization; transition from solid to liquid to gas.

ΔH = -

Exothermic, example: solidification, condensation; transition from gas to liquid to solid.

Vaporization

AHvap > 0

Condensation

-AHvap < 0

Sublimation

AHsub > 0

Fusion

AHfus > 0

Solidification

-AHfus < 0

Enthalpy (H)

The amount of energy existing in substances during chemical reactions.

ΔH

The change in Enthalpy, as absolute enthalpy cannot be measured.