How does molecular attraction affect the amount of energy needed to create a phase change. Think about low, medium, and high attraction molecules.

When considering phase changes, the closer molecules are to one another, the stronger the intermolecular forces. Good! For any given substance, intermolecular forces will be greatest in the solid state and weakest in the gas state.

In the case of melting, added energy is used to break the bonds between the molecules. ... If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance. The example we will use here is ice melting into water.

the product of the pressure and volume is also constant