Question

What is the balanced chemical equation for this reaction: when gaseous chlorine reacts with an aqueous solution of potassium bromide to form liquid bromine and an aqueous solution of potassium chloride?

Answer 1

Hint: Balancing of the reaction means that the number of moles of each of the atoms involved in that very chemical reaction should have the equal no of moles on both sides i.e. the reactants and the product sides. Now balance the equation.

Complete answer:
First, we should know what a chemical reaction is. The reaction in which the reactants react with each other to form two or more products is known as the chemical reaction. The reactants are written on the left hand side and the products are written on the right-hand side and there is an arrow from left to the right symbolizing a complete chemical reaction.
Example: consider the general reaction as:
$A+B\to C+D$
Here, A and B are the reactants and C and D are the products and the arrow indicates the direction in which the chemical reaction occurs.
In this, the chemical equation is said to be balanced, when it has the equal no of atoms of each element on both the sides i.e. on the reactant and the products side.
Now, we will balance the given chemical reaction with the equal no of moles on both the reactant and the product side.
Now considering the statement as;
When gaseous chlorine is made to undergo reaction with the aqueous solution of potassium bromide, it results in the formation of bromine and potassium chloride.
The reaction occurs as;-
$C{{l}_{2}}+KBr\to KCl+B{{r}_{2}}\uparrow $ ----------(1)

The no of moles of eachatom on the reactant side	The no of moles of eachatom on the product side
Cl=2	Cl=1
K=1	K=1
Br=1	Br=2

 Since, there are 2 Cl on the reactant side and 2 Br on the product side , then we will add 2 in front of KCl and in front of KBr in eq (1), we get;
$C{{l}_{2}}+2KBr\to 2KCl+B{{r}_{2}}\uparrow $-------(2)
So, equation (2) is the fully balanced equation.
Thus, when gaseous chlorine reacts with an aqueous solution of potassium bromide to form liquid bromine and an aqueous solution of potassium chloride, the balanced chemical equation for the reaction is as;
$C{{l}_{2}}+2KBr\to 2KCl+B{{r}_{2}}\uparrow $

Note:
After balancing, check whether the no of moles of each atom are same on both the sides or not and balancing the chemical reaction is very important because it helps to conserve the mass of that very atom/substance or the compound.