Question

How many grams of magnesium phosphate $(M{g_3}{(P{O_4})_2})$ will be produced from the reaction of magnesium with $54.21g$ of phosphoric acid $({H_3}P{O_4})$?

Answer 1

The stoichiometry of the reaction gives us an idea about the amount of reactant reacts in a particular ratio of mole or mass or number. The stoichiometry ratio of each and every reaction is fixed and it follows the Law of definite proportion or constant proportion.

Complete step by step answer:
During the chemical reaction, we follow the law of conservation of mass.
According to the law, during the chemical reaction, mass remains constant. i.e., mass of the reactant as well as mass of product are the same.
To follow the above law, we balance the chemical reaction in which we balance all the atoms included in the reactant as well as in the product.
A chemical reaction which contains more than one reactant to form a product, both reactants must combine in a definite ratio to form the product. Each and every reactant combines either in a fixed mole ratio or in a mass ratio to form a product.

Balanced chemical equation: -
$3Mg + 2{H_3}P{O_4} \to M{g_3}{(P{O_4})_2} + 3{H_2}$
In the above equation, both Magnesium and Phosphoric acid $({H_3}P{O_4})$ combines in a fixed mole ratio of $3:2$ to form magnesium phosphate $M{g_3}{(P{O_4})_2})$ and 3 moles of Hydrogen gas.
The above reaction is balanced according to the Law of conservation of mass, where the mass of the reactant side is equal to the mass of the product side. According to the reaction, three moles of magnesium combines with two moles of phosphoric acid to form products.
In the given question, $52.41$ grams of phosphoric acid is given.
Gram molecular mass of phosphoric acid $= 98gram/mol,$
Gram molecular mass of magnesium $= 24gram/mol$
So according to the stoichiometry of the reaction
$2 \times 98$ gram phosphoric acid produces 262 grams Magnesium phosphate $M{g_3}{(P{O_4})_2})$
So, 54.21 gram of phosphoric acid produces $\dfrac{{262 \times 54.21}}{{2 \times 98}}\,\, = \,72.46$gram Magnesium phosphate $M{g_3}{(P{O_4})_2})$
Final answer:
The final answer is $72.46$ gram of Magnesium phosphate $M{g_3}{(P{O_4})_2})$ is obtained by the reaction of $52.41$ gram of phosphoric acid with excess of Magnesium

Note:
In every reaction, atom conservation is very important. In any chemical reaction every time conservation of atom is there, by the help of atom conservation we can balance any chemical reaction.