Unit Two - Molecular and Ionic Compounds Structure / Properties Flashcards
What is a sea of electrons
Electron that flow freely in the d orbital. These conduct well because of the delocalized electrons.
What is an interstitial alloy
Two atoms of very different sizes
What is a substitutional alloy
Similar sized atoms (replace eachother)
Hauhns Law
Electrons will ocuppy higher level first
What are the variables of of AXE
A ( central atom)
X (number of bonds)
E (number of unpaired electrons)
Steps to dtermining a resonance
Step One: Determine the formal charge (FC = # valence - ( # bonds + unbonded e-)
Step Two: Resonance is the one with the least formal charge
Covalent bond characteristics
-Low melting points
-Conductivity low
Ionic bond characteristics
-High melting / boiling points
-Conduct when aqueous
Polar bonds
Unequal sharing or electrons
Non-Polar bonds
Equal sharing in an overlapting orbitals
Network covalent bonds
-High melting points
-Brittle / hard
-Do not conduct well
Ex. SiO2
Intermolecular distance: general graph
Start: to close because of repulsion
Middle: Potential energy the lowest and most stable
End: no attraction becuase they are to far apart
Intermolecular distance: chane in size of atom graph
A bigger molecule increases the distance between the nucleus, meaning the bonds are easier to break and a lower potential energy is present.
Smaller molecules have nucleuses closer together, they are harder to break and potential energy is higher.
Intermolecular distance: change in bonds graph
Single bonds have a greater distance (start on the left) they are easier to break so they have a lower potential energy.
Double bonds have a smaller distance (start on the right), they are harder to break so they have a higher potential energy.
