Solubility

Enthalpy

What is Enthalpy? 

The following video does go further than you need, but gives a good explanation:

Enthalpy: Understanding why enthalpy can be viewed as "heat content" in a constant pressure system.

Enthalpy of Formation

Heat of Formation: Standard heat of formation or standard enthalpy change of formation.

Enthalpy of Formation values can be very useful for calculating the enthalpy change in a reaction. There are two ways to do this:

METHOD ONE

• Find the sum of the enthalpies of formation of the products.
• Find the sum of the enthalpies of formation of the reactants.
• Subtract the latter from the former.

METHOD TWO

• Write out the equations that each enthalpy of formation represents
• Use Hess' Law

Hess's Law and Reaction Enthalpy Change: Using Hess's Law and standard heats of formation to determine the enthalpy change for reactions

Enthalpy of Fusion and Enthalpy of Vaporisation

Intermolecular Forces

Last year, we learned about ionic bonds, covalent bonds, van der Waals forces and metallic bonds. We still need to know about these this year, but now need to understand hydrogen bonds and need to know more about van der Waals forces.