Question

How do you balance:
\[{{H}_{3}}P{{O}_{4}}+Mg{{(OH)}_{2}}\to M{{g}_{3}}{{(P{{O}_{4}})}_{2}}+{{H}_{2}}O\]

Answer 1

Hint: To solve this type of question it is important to understand the reaction condition and the type of reaction. And the most important step is to balance the chemical reaction.

Complete step by step answer:
- The reaction given in the question is mentioned below:
\[{{H}_{3}}P{{O}_{4}}+Mg{{(OH)}_{2}}\to M{{g}_{3}}{{(P{{O}_{4}})}_{2}}+{{H}_{2}}O\]
- Now we have to check whether the reaction is balanced or not. Law of conservation of mass states that both the reactants and products have the same mass. And we know that in a chemical reaction mass can neither be created nor be destroyed. Initially we will check whether the given reactants and products are correct or not. There are coefficients which are used to balance the reaction. We should remember that the subscript near each element cannot be changed; we can only change the coefficients to balance the reaction.
- So here if we check there is 1 magnesium on the right-hand side and 3 magnesium atoms on the left-hand side of the reaction. Similarly, there are 5 hydrogens on the right hand side and 2 hydrogen atoms on the left-hand side of the reaction respectively and 6 oxygen atoms on the right-hand side and 9 oxygen atoms on the left hand side of the reaction respectively. And there is 1 sulphur atom on the right hand side and 2 phosphorus atoms on the left-hand side of the reaction.
- To balance magnesium, we will multiply the magnesium molecule on the right-hand side by 3. To balance hydrogen atom, we will multiply the hydrogen molecule on right-hand side i.e. ${{H}_{3}}P{{O}_{4}}$ by 2 and $Mg{{(OH)}_{2}}$ by 3 and on the left hand side by 6.
The balanced chemical reaction is:
\[2{{H}_{3}}P{{O}_{4}}+3Mg{{(OH)}_{2}}\to M{{g}_{3}}{{(P{{O}_{4}})}_{2}}+6{{H}_{2}}O\]

Note: The chemical equation can also be written in ionic form. But the equation has to be balanced by balancing mass and charge on the reactant and product side. We have to follow the law of conservation of charge also.