LEC 4 Flashcards
____ can be used to predict the
nature of the bond.
Generally, the difference is:
• 0.0 – 0.4 ____ bond
• 0.4 – 1.78 ____ bond
• 1.78 > _____ bond
Electronegativities
Non polar covalent bond
Polar covalent bond
Ionic bond
_____
– Sharing of a pair of electrons between two atoms
• Examples: HF, Cl2, H2O
• ____
– Sharing of 2 pairs of electrons between two atoms
• Examples: O2, CO2
•____
– Sharing of 3 pairs of electrons between two atoms
• Examples: N2
, HCN
Single bond
Double bond
Triple bond
– Formed when electrons are unequally shared between two atoms
• e.g. H2O, HF, NH3
Polar bond
– Have an equal attraction or affinity for electrons
• e.g. H2, N2, Cl2, Br2
Non polar bond
– bonds between atoms which are formed through sharing of electrons
– between two non-metal atoms through sharing of pairs of electrons
Covalent bond
– Metals can form bonds with other metals, but it is neither covalent or ionic and they cannot share
electrons to form an octet of electrons around each atom
– The valence electrons are ____, which means they are free to move from one atom to the next
Metallic bond
Delocalized
METALLIC PROPERTIES
• Metals are ___
• Metals have high ____ and ____ points
• Metals are good ____ of ____
• Metals are ____ and ____
Dense
High melting
Boiling point
Good conductors of electricity
Malleable and ductile
– form from the electrostatic attraction
between oppositely charged ions
– Atoms become ionic by losing or gaining electrons from the atom it is bonding with
Ionic bonds
- Elements tend to combine in such a way that each atom has eight electrons in its valence shell giving it
the same electron configuration as a noble gas
(exception: Hydrogen with 2 max electrons in its
outershell)
Octet rule
– Electrons in the outermost
energy level of an atom
– Determine what kind of chemical
bonds the atom can form
Valence electrons
– Are electrostatic forces of
attraction that hold atoms
together
Chemical bonds
Also known as electron-dot structures
Lewis structure
