Thursday 13 June 2013

Enthalpy

What is Enthalpy? 

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


Enthalpy 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

Friday 7 June 2013

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.