Reactions Flashcards
Define enthalpy of formation
Enthalpy associated with reactions where one mole of a compound is formed from a reaction between the elements that make it up under standard conditions
Define enthalpy of neutralisation
Enthalpy associated with reactions where one mole of water is formed from a reaction between an acid and a base under standard conditions
Define enthalpy of solution
Enthalpy associated with reactions where one mole of a solute is dissolved in excess solvent to form an infinitely dilute solution (solution which exhibits no enthalpy change when more solute is dissolved)
Define enthalpy of combustion
Enthalpy associated with reactions where one mole of a substance is combusted in excess oxygen
Describe why the experimental process for finding the enthalpy of neutralisation is relatively precise
Reaction between acid and base is fairly quick but energy still lost to air and thermometer
Describe why the experimental process for finding the enthalpy of combustion is not precise
A lot of heat lost to surroundings
How long should you keep stirring the solution in the enthalpy of solution experiment?
5 minutes within which quite an amount of heat is lost
What should be the allowed approximate maximum change in temperature during an enthalpy of combustion experiment
10 degrees
Formula for enthalpy change
(-mcΔT)/m/mr
Using enthalpy of formation to calculate enthalpy of reaction
elements -> reactants -> products ->elements again
Using enthalpy of solution to calculate enthalpy of hydration
Anhydrous compound + water -> hydrated compound
Both anhydrous Compound + water and hydrated compound each -> aqueous solution
Using enthalpy of combustion to calculate enthalpy of formation
elements + oxygen form compound + oxygen which both lead to water and carbon dioxide
