Chapter 8 Chemical Bonding Flashcards
3 types of bonds
Ionic- electrostatic attraction between ions
Covalent- sharing of electrons
Metallic- metal atoms bonded to other atoms
Lattice Energy
Energy required to completely separate a mile of a solid ionic compound into its gaseous ions
Energy associated with electrostatic interactions is governed by
Coulomb’s law
Lattice energy increases with ________ and decreases with ————
Charge on ions, decreasing size of ions
Electronegativity
The ability of atoms in a molecule to attract electrons to themselves
Electronegativity increases as you go
Left to right and bottom to top
When two atoms share electrons unequally a _______ results
Bond dipole
The greater the difference in ________ the more polar the bond
Electronegativity
Writing Lewis structures steps
- Find the sum of all valence electrons in the molecule or polyatomic ion
- The central atom is the least electronegative element that isn’t hydrogen. Connect the outer atoms to it by single bonds
- Fill the octets of the outer atoms
- Fill the octet of the central atom
- If you run out of electrons before the central atom has an octet, form multiple bonds until it does
Formal charge
Count the electrons in lone pairs and half the electrons it shares with other atoms.
Subtract that from the number of valence electrons for that atom
The best Lewis structure is
The one with the fewest charges
Puts a negative charge on the most electronegative atom
3 types of ions or molecules that do not follow the octet rule
Odd number of electrons
Less than an octet
More than an octet
If filling the octet of the central atom results in a negative charge on the central atom and a _________ on the more electronegative outer atom then_______
Positive charge, don’t fill the octet of the central atom
When the central atom is on the ______ row or below and expanding its octet eliminates some formal charges _____
Third, do so
The strength required to break a bond
Bond enthalpy
