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Chapter 6 - Coggle Diagram
Chapter 6
features of bonds:
distance (pm, A, nm)
angle
energy (bond energy = stability)
order (1, 2 or 3)
types of chemical bonds
Met + NonMet
ionic bonding (>1.7)
hold by electrostatic interaction
Met + Met
metallic bonding
NonMet + NonMet
covalent bonding
Ionic Bonds
the strenght is due to F = q1*q2 / r^2
e- are taken in order to reach the octet
ionic compounds
electrical insulators (cannot move --> no Dipole)
Conductive molten or in solution
high melting and boiling points
Hardness
Rigidness
Fragility
soluble in water and polar liquids
premises to explain the formation of ionic bonds
1) a state function (such as Entropy (S), Enthalpy (H), Internal Energy (U) does not depend on the path; is unique for a state.
(Enthalpy H is the Heat exchanged at constant pressure by the sistem (Hfin - Hin = dH); >0 is endothermic, <0 is exothermic.
2)
Hess Law
: the dH (change in enthalpy) of a reaction is the same independently on the path followed (could also be a sum of many steps)
Born Haber Cycle
see graphs, we sum every steps to get the final dH:
ex: Li + 1/2 F2
dHin (>0) + dHsubl (>0) + BE(Bonding Energy (>0) + IE (Ionization Energy) (>0) + EA (Electron Affinity) (<0) + Lattice Energy (<<0)
Lattice Enthalpy is directly prop to q^2 and inversely prop to r^2
Lattice Energy decrease with groups and down periods (since size increase)