Question

What will be the values of the coefficients x, y and z if the given reaction is balanced?

${\text{xFeCl}}_3+\text{yMgO}\to {\text{Fe}}_{\text{2}}{\text{O}}_3+{\text{zMgCl}}_2$

• A. x = 2, y = 4, z = 3
• B. x = 2, y = 3, z = 3
• C. x = 3, y = 2, z = 3
• D. x = 3, y = 2, z = 2

Answer 1

The correct option is B x = 2, y = 3, z = 3

To find the value of x, y and z, we need to balance the given equation.
Number of Fe atoms on the reactant side: 1
Number of Fe atoms on the product side: 2
So we will multiply 2 on the left side to $FeC{l}_3$. Hence it will become;

$2FeC{l}_3+MgO\to F{e}_2{O}_3+MgC{l}_2$

Number of Cl atoms on the reactant side: 6 (i.e. 2x3)
Number of Cl atoms on the product side: 2

So we will multiply 3 on the right side to $MgC{l}_2$. Hence it will become;

$2FeC{l}_3+MgO\to F{e}_2{O}_3+3MgC{l}_2$

Now, the number of Mg atoms are not balanced. In order to balance it, we will multiply 3 to MgO.

$2FeC{l}_3+3MgO\to F{e}_2{O}_3+3MgC{l}_2$

From the above balanced equation the value of x, y and z, w are 2, 3, and 3 respectively.