4.2 Net Ionic Equations

To show only the ions and molecules directly involved in a chemical reaction

To list all reactants and products, including spectator ions

To balance the number of atoms on both sides of the equation

To show the physical states of all substances involved

A chemical equation represents a physical change.

A chemical equation shows the rearrangement of atoms into new combinations.

A chemical equation must have unequal numbers of atoms on both sides.

A chemical equation demonstrates that energy is always released.

(aq) for aqueous

(g) for gas

(l) for liquid

(m) for molten

Count the atoms on each side of the equation

Write out the equation

Change a coefficient to make one element correct

Compare the counts

Sodium, potassium, ammonium, and nitrate

Calcium, magnesium, and sulfate

Iron, copper, and phosphate

Chloride, bromide, and iodide

Na+ and NO3-

Pb2+ and Cl-

Na+ and Cl-

Pb2+ and NO3-

To show only the ions and molecules directly involved in a chemical reaction

To list all reactants and products, including spectator ions

To balance the number of atoms on both sides of the equation

To represent only physical changes in matter