Question

question 10. 106.5 g of hydrochloric acid react with an unknown amount of ammonia to produce 156.3 g of ammonium chloride. how many grams of ammonia reacted? is the law of conservation of mass observed in the reaction? justify your answer.

Explanation:

Step1: Write the chemical equation

The reaction is $HCl + NH_3
ightarrow NH_4Cl$.

Step2: Apply the law of conservation of mass

According to the law of conservation of mass, mass of reactants = mass of products. Let the mass of ammonia be $x$ grams. The mass of $HCl$ is $106.5$ g and the mass of $NH_4Cl$ is $156.3$ g. So, $106.5 + x=156.3$.

Step3: Solve for the mass of ammonia

Subtract $106.5$ from both sides of the equation: $x = 156.3 - 106.5$.
$x=49.8$ g.

Step4: Check the law of conservation of mass

Mass of reactants: $106.5$ g ($HCl$) + $49.8$ g ($NH_3$)=$156.3$ g. Mass of product is $156.3$ g ($NH_4Cl$). Since mass of reactants = mass of products, the law of conservation of mass is observed.

Answer:

49.8 g of ammonia reacted and the law of conservation of mass is observed because the sum of the masses of the reactants ($106.5$ g of $HCl$ and $49.8$ g of $NH_3$) is equal to the mass of the product ($156.3$ g of $NH_4Cl$).