How To Write Skeleton Equations

Chemistry students routinely use skeleton equations in order to balance the equations for chemical reactions. The reactants of the equation are typically on the left-hand side of the equation and the products are on the right-hand side, which gives the equation its basic structure. This is why it is called a "skeleton" equation. To make the equation complete, you need to solve for the correct coefficients for each of the chemicals, which indicate the relative amounts of each.

Step 1

Determine the reactants for the equation and write them on the left-hand side, separated by a plus sign. Add an arrow after the reactants. For instance, if the reactants were calcium chloride and sodium sulfate, you would write:

CaCl(2) + Na(2)SO(4) —>

Step 2

Write the appropriate products on the right-hand side of the arrow, separated by a plus sign. For this example, the products are calcium sulfate and sodium chloride.

CaCl(2) + Na(2)SO(4) —> CaSO(4) + NaCl

You can tell this is a skeleton equation because the number of atoms of sodium and chlorine are not equal on both sides.

Step 3

Add the notation to indicate the state of the chemicals. They will typically be solid (s), liquid (l), gas (g) or aqueous solution (aq). In this example, two aqueous solutions on the left combine to form an aqueous solution and a solid precipitate on the right.

CaCl(2) (aq) + Na(2)SO(4) (aq) —> CaSO(4) (s) + NaCl (aq)