I have two questions, this is a take home review in my university course

List the most important (strongest) intermolecular forces that must be overcome to 

 

a) remove water of hydration from NiSO4 7H2O

b) vaporize liquid CH3 OH

 

 

The second question is..

 

Consider what happens when solid CsI dissolves in liquid CH3OH

 

a) What type of attractive forces must be overcome in the liquid CH3OH?

b) What type of forces must be onvercome in the solid CsI?

c) What type of attractive forces are important when CsI dissolves in liquid CH3OH? 

 

Any help is greatly appriciated! 

I'm sure this is a little late but to answer these you need to know what intermolecular versus intramolecular is.  Intermolecular is like interstate highways go between states.  intermolecular forces are between separate molecules.  Intramolecular are between the atoms within a molecule which is to say they are chemical bonds.

So for the intermolecular forces they are based on charge attractions for the most part.  You could look these up in your book or online: ion - ion, ion - dipole, ion - induced dipole, dipole - dipole, dipole - induced dipole.  The last type (other than charge attraction forces) is the Vanderwaals forces that are related to the discovery of quantum mechanics but they are forces in non-polar things.  They are bigger if there is more electrons in each molecule so things with more formula weight have more Vanderwaals because they have more electrons.  I once thought it was gravity from more weight but I don't think so now; it is a quantum mechanics thing and the 'mechanism' of that is a bit a mystery to me.

So for first question:

Identify which are the molecules.

Identify which forces are possible between molecules.

Which forces are strongest?  

You will need to read enough(on how to identify types of molecules and about each force eg vanderwaals, or ion - dipole etc) to be able to do those things.

Hint for the first one is to know what a complex ion is.  And thereby they will talk about what waters of hydration are.  tagword could be 'ligand' and 'complex ions'

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