2.1-2.4 Flashcards
Ionic bonds
Metals transfer electrons to non-metals and the two form bonds due to the electrostatic attractions between them.
Covalent bonds
One non-metal atom shares one or more pairs of electrons with another non-metal atom so that both acquire full octets.
Molecules
Two or more non-metals bonded together - nonpolar or polar covalently - to form a compound.
Ionic vs covalent bonding
Metal + nonmetal is generally ionic
Two nonmetals is generally covalent
Three main properties of ionic solids
(1) Strong bonds
(2) Cleave along planes
(3) Solubility and conductivity
Ionic solids: strong bonds
(1) Strong coulombic forces of attraction between cations and anions
(2) High melting points
(3) Very hard
(4) Low volatility
Ionic solids: cleave along planes
(1) Ions are arranged in a repetitive pattern to maximize attractive and minimize repulsive forces
(2) Not malleable or ductile
Ionic solids: solubility and conductivity
(1) Mostly soluble in polar solvents
(2) Conduct electricity only when molten or dissolved
Three main properties of covalent bonds
(1) Lower melting and boiling point than ionic compounds
(2) Soft and flexible
(3) Most do not conduct electricity when dissolved in water
Polyatomic ions
Metals and non-metals or non-metals bond to form a polyatomic ion or polar covalent
Crystalline solids
Ionic compounds do not exist as individual units but are arranged in a 3D repititious pattern.
How are ions in a solid arranged?
To maximize Coulombic forces of attraction and minimize repulsion between ions with like charges
Metallic solid
Non-covalent bonding results from attractions between Nuclei and delocalized valence electrons
Five properties of metallic bonding
(1) Conduct electricity
(2) Conduct heat
(3) Malleable and ductile
(4) Lack directional bonds
(5) Localed inner core, free valence electrons
Solution
Homogeneous mixture of 2+ substanc
