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Ionic Bond The electrostatic force that holds oppositely charged particles together in an ionic compound is called an ionic bond. Most ionic compounds are called salts.
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Ionic Bonds
Chemical Bonds The force that holds two atoms together
is called a chemical bond.
Ionic Bond The electrostatic force that holds
oppositely charged particles together in an ionic compound is called an ionic bond.
Most ionic compounds are called salts.
Properties of Ionic Compounds During the formation of an ionic
compound, the positive and negative ions are packed into a regular repeating pattern that balances the forces of attraction and repulsion between the ions. This particle packing forms an ionic crystal lattice, a three-dimensional geometric arrangement of particles.
Ionic crystals have high melting points and boiling points because the ionic bonds are strong.
When dissolved in water, ionic compounds are electrical conductors because the ions are free to move . An ionic compound whose aqueous solution conducts electric current is called an electrolyte.
During any chemical reaction, energy is either absorbed or released. Endothermic or exothermic
Energy changes also occur during the formation of ionic bonds from the ions formed during a chemical reaction.
The energy required to separate one mole of the ions of an ionic compound is referred to as the lattice energy.
Formulas for Ionic Compounds The simplest ratio of the ions represented in
an ionic compound is called a formula unit. A formula unit for magnesium chloride is
MgCl2. Because the total number of electrons
gained by the nonmetallic atoms must equal the total number of electrons lost by the metallic atoms, the overall charge of a formula unit is zero.
A monatomic ion is a one-atom ion, such as Mg2+ or Br-.
The charge is determined by the location of the element on the periodic table.
The transition metals can form several different positive ions.
Polyatomic ions are ions made up of more than one atom.
The charge given to a polyatomic ion applies to the entire group of atoms.
Naming Ionic Compounds 1. Name the cation first and anion second. 2. Monatomic cations use the element name. Monatomic anions use the element name
plus the suffix –ide. Transition metals and metals on the right side
of the periodic table often have more than one charge; therefore, roman numerals are used to identify the charge.
Use the polyatomic ion name.
