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IONIC BONDING. 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
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IONIC BONDING 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
Solutions • When ionic compounds are put in water, they dissove into ions:
Examples: OH-1 = hydroxide NO3-1 = nitrate PO4-3 = phosphate SO4-2 = sulfate They behave just like single atom ions. Polyatomic ions: are groups of atoms bonded together with a charge.
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