What are the rules for writing ionic equations?

Ionic equations are written to represent the ions involved in a chemical reaction, showing only the particles that change during the reaction.

Writing ionic equations involves several rules. Firstly, you need to write the balanced molecular equation for the reaction. This equation includes all the reactants and products in their molecular forms. For example, if sodium chloride reacts with silver nitrate to form sodium nitrate and silver chloride, the balanced molecular equation would be NaCl + AgNO3 → NaNO3 + AgCl.

Next, you need to write the total ionic equation. This involves breaking all the strong electrolytes into their ions. Strong electrolytes include strong acids, strong bases, and soluble salts. In our example, the total ionic equation would be Na+ + Cl- + Ag+ + NO3- → Na+ + NO3- + AgCl.

The third step is to identify and cancel out the spectator ions. These are ions that appear on both sides of the equation and do not participate in the reaction. In our example, the spectator ions are Na+ and NO3-. After cancelling these out, we are left with the net ionic equation: Cl- + Ag+ → AgCl.

Remember, the states of the substances (solid, liquid, gas, or aqueous) should be included in the equations. Also, charges and atoms should be balanced in the final net ionic equation.

In summary, writing ionic equations involves writing the balanced molecular equation, breaking down strong electrolytes into their ions to form the total ionic equation, and then cancelling out spectator ions to get the net ionic equation. This process helps to clearly show the actual chemical changes happening in the reaction.