Question

Balance the equation $N{a_2}C{O_3} + HCl \to NaCl + C{O_2} + {H_2}O$ .

Answer 1

A chemical equation in which number of atoms of all the elements are equal on both reactants and products side is known as balanced chemical reaction and if the number of atoms of all the elements on both sides (products and reactants) are not equal then the reaction is known as unbalanced chemical reaction.

Complete answer:
So, we know that, in a chemical equation, if the number of atoms of all the elements are equal on both reactants and products side it is a balanced chemical equation otherwise it is an unbalanced chemical equation.
We need to balance an unbalanced chemical equation in order to follow the “law of conservation of mass” which states that mass can neither be created nor be destroyed.
Now, if we look at given chemical equation:
$N{a_2}C{O_3} + HCl \to NaCl + C{O_2} + {H_2}O$
First, we will make a table and count the number of atoms of each element on both reactant and product sides.

Element	Reactant side	Product side
Sodium, Na	$2$	$1$
Carbon, C	$1$	$1$
Oxygen, O	$3$	$3$
Hydrogen, H	$1$	$2$
Chlorine, Cl	$1$	$1$

Here, we can see that sodium and hydrogen atoms are not balanced.
First, we will balance the sodium atoms by multiplying $NaCl$ in the product side with $2$ .
Hence, the equation becomes:-
$N{a_2}C{O_3} + HCl \to 2NaCl + C{O_2} + {H_2}O$

Element	Reactant side	Product side
Sodium, Na	$2$	$2$
Carbon, C	$1$	$1$
Oxygen, O	$3$	$3$
Hydrogen, H	$1$	$2$
Chlorine, Cl	$1$	$2$

Now, hydrogen and chlorine are unbalanced. So, to balance them, we will multiply $HCl$ in reactions with 2.
$N{a_2}C{O_3} + 2HCl \to 2NaCl + C{O_2} + {H_2}O$

Element	Reactant side	Product side
Sodium, Na	$2$	$2$
Carbon, C	$1$	$1$
Oxygen, O	$3$	$3$
Hydrogen, H	$2$	$2$
Chlorine, Cl	$2$	$2$

Hence, now all the atoms in reactant and product sides are equal so the balanced chemical equation is:
$N{a_2}C{O_3} + 2HCl \to 2NaCl + C{O_2} + {H_2}O$

Note:
While balancing any element or equation, remember it should be multiplied a number as we have done in the above case. Never try balancing an equation by changing the subscripts otherwise the molecular formula of the compound will change and it will not be the same as the compound given in the equation.