The Metal – Nonmetal
Bond
When a metal and nonmetal come
together, a pair of electrons acts as a
bond. They each become ions.
The Rules:
• Metal first, nonmetal second
• Nonmetal ion becomes ‘ide’
• Metal is positve, nonmetal is
negative
• Charges must balance to zero
• Formula uses a subscript to balance
charges
• Example: MgCl2 ; Na2O
Practice:
Sodium and
fluorine
Barium and
iodine
lithium and
phosphorus
Aluminum and
oxygen
Beryllium and
oxygen
Calcium and
nitrogen
Answers:
Sodium and
fluorine
Barium and
iodine
lithium and
phosphorus
NaF
BaI2
Li3P
Aluminum and Beryllium and
oxygen
oxygen
Al2O3
BeO
Calcium and
nitrogen
Ca3N2
Solutions
• When ionic compounds are put in water,
they dissove into ions:
Polyatomic ions: are groups of
atoms bonded together with a
charge.
Examples:
• They behave
OH-1 = hydroxide
just like
NO3-1 = nitrate
single atom
PO4-3 = phosphate
ions.
•
•
•
•
• SO4-2 = sulfate
Practice: Use polyatomic ions
just like any other ion; But when
you have more than one , use
parentheses.
•
•
•
•
barium hydroxide= Ba(OH)2
strontium nitrate=
lithium phosphate
potassium sulfate
• Notice parentheses show multiple ions.
Answers:
•
•
•
•
barium hydroxide Ba(OH)2
strontium nitrate Sr(NO3)2
lithium phosphate Li3PO4
potassium sulfate K2SO4
Transition metals: Metals that
have more than one possible
charge:
•
•
•
•
Cobalt: Co+2, Co+3
Copper: Cu+, Cu+2
Iron: Fe+2, Fe+3
Lead: Pb+2, Pb+4
• When writing the names,
always use roman numerals to
show the charge.
Examples:
•
•
•
•
Cobalt (II) Co+2, Cobalt (III) Co+3
Copper(I), Cu+, or Copper (II), Cu+2
Iron(II) Fe+2, or iron (III), Fe+3
Lead(II), Pb+2, or lead (IV), Pb+4
• Each of these behaves
completely different than the
others!!! Show the numbers!
Practice!
Lead (IV) hydroxide
Copper (II) nitrate
CoPO4
Fe2(SO4)3
Answers:
• Lead(IV) hydroxide Pb(OH)4
• Copper(II) nitrate Cu(NO3)2
• Cobalt (III) phosphate CoPO4
• Iron (III) sulfate Fe2(SO4)3