Topic 6 : Thermodynamics Flashcards
(8 cards)
What is the difference between endothermic and exothermic reactions?
Endothermic reactions take in energy, while exothermic reactions release energy.
What does enthalpy (ΔH) measure?
Enthalpy is a measure of the energy stored in the system.
What are standard enthalpy changes (ΔH°)?
Standard enthalpy changes are heat energy changes measured at constant pressure, specifically at 100 kPa and 298K (25°C).
What is ΔH° formation?
ΔH° formation is the enthalpy change when 1 mole of a compound is formed from its elements in their standard state under standard conditions.
What is ΔH° combustion?
ΔH° combustion is the enthalpy change that takes place when 1 mole of a substance is completely combusted.
What is the enthalpy change for neutralization?
The enthalpy change for neutralization occurs when one mole of water is produced by the neutralization of an acid and alkali.
How is ΔH calculated?
ΔH = products - reactants.
What does the Law of Conservation of Energy state?
The Law of Conservation of Energy states that energy is never lost or destroyed; reactions will often exchange heat energy between the system and surroundings.
