Question

How do you balance $NaOH+{{H}_{2}}S{{O}_{4}}\to N{{a}_{2}}S{{O}_{4}}+{{H}_{2}}O$

Answer 1

The given chemical equation can be balanced by balancing both the sides atoms. For this start balancing with the most complicated formula. Then balance all other atoms except $H$ and $O$. Then proceed to balance the $H\,and\,O$ atoms. Finally check whether the equation is balanced or not.

Complete step-by-step answer: Step 1: Start balancing with the most complex compound involved in the reaction. So, let us start with $NaOH$.
We should keep in mind that for ease, we will balance O and H at last. So, let us start with balancing sodium $\left( Na \right)$.
In the reaction we see that there is $1\text{ Na}$ atom on the LHS whereas RHS has $\text{2 Na}$ atoms. So, in order to balance the sodium atoms, we will put $2$ in front of $NaOH$ as shown below.
$2NaOH+{{H}_{2}}S{{O}_{4}}\to N{{a}_{2}}S{{O}_{4}}+{{H}_{2}}O$. (equation 1)
Now we can see that both LHS and RHS have 2 sodium atoms. Thus, sodium is balanced.
Step2: Now let us move to sulfur. We see that both LHS and RHS have $1\text{ S}$ atoms. Thus, sulfur is already balanced.
Till now all the atoms except H and O are balanced.
Step 3: Now let us balance Oxygen (O atom)
From equation 1, we can see that there are, total $\text{6 O}$ atoms on LHS and RHS has only $5\text{ O}$ atoms. So, to balance oxygen atoms we will add $2$ in front of ${{H}_{2}}O$ as shown in the reaction below.
$2NaOH+{{H}_{2}}S{{O}_{4}}\to N{{a}_{2}}S{{O}_{4}}+2{{H}_{2}}O$ (equation 2)
Now, we can see that LHS and RHS both have $6\text{ O}$atoms.
Step4: Now, the only atom left is Hydrogen. If we look carefully in equation 2, we can clearly see that hydrogen itself is balanced. This is the only reason that it is suggested to balance O and H atoms at last because in many reactions they automatically get balanced, after a few steps.
Thus, the given reaction is Balanced Completely and the balanced chemical reaction can be written as
$2NaOH+{{H}_{2}}S{{O}_{4}}\to N{{a}_{2}}S{{O}_{4}}+2{{H}_{2}}O$
The given reaction is a type of neutralization reaction. In such reactions acid and a base react with each other and form salt along with water molecules. Such reactions have found their uses in Acid base titrations, wastewater treatment, Controlling soil pH etc.

Note: Once the reaction is balanced, cross check it by counting the number of atoms on RHS and LHS. If atoms both the sides are balanced, then the equation becomes balanced automatically. Always express the fraction in whole numbers while balancing a given reaction.