. Now the partly balanced equation becomes – Fe + H O → Fe O + H Step IV: Fe and H atoms are still not balanced. Pick any of these elements to proceed further. Let us balance hydrogen atoms in the partly balanced equation.
To equalise the number of H atoms, make the number of molecules of hydrogen as four on the RHS. Step III: It is often convenient to start balancing with the compound that contains the maximum number of atoms. It may be a reactant or a product. In that compound, select the element which has the maximum number of atoms.
Using these criteria, we select Fe O and the element oxygen in it. There are four oxygen atoms on the RHS and only one on the LHS. To balance the oxygen atoms – The equation would be – Fe + H O → Fe O + H Atoms of In reactants In products oxygen Initial (in H O) (in Fe O ) To balance × Atoms of In reactants In products hydrogen Initial (in H O) (in H ) To balance × ( . ) (partly balanced equation) ( .
) (partly balanced equation) To equalise Fe, we take three atoms of Fe on the LHS. Fe + H O → Fe O + H ( . ) Step VI: Finally, to check the correctness of the balanced equation, we count atoms of each element on both sides of the equation. 3Fe + 4H O → Fe O + 4H The numbers of atoms of elements on both sides of Eq.
( . ) are equal. This equation is now balanced. This method of balancing chemical equations is called hit-and-trial method as we make trials to balance the equation by using the smallest whole number coefficient.
Step VII: Writing Symbols of Physical States Writing Symbols of Physical States Writing Symbols of Physical States Writing Symbols