When 5.0 g of tin reacts with hydrochloric acid, the mass of the products, tin chloride and hydrogen, totals 8.1 g. How many grams of hydrochloric acid were used?

1 Answer
Aug 3, 2017

Answer:

The mass of hydrochloric acid that was used is #"3.1 g"#.

Explanation:

The law of conservation of matter/mass states that matter is neither created nor destroyed during a chemical equation in a closed system. So the total mass of the reactants equals the mass of the products.

So, if the mass of the products totals #"8.1 g"#, then you know that the total mass of the reactants must be equal to the total mass of the products. If the mass of the reactant tin is #"5.0 g"#, then the mass of the reactant hydrochloric acid is the difference between the total mass of the products and the mass of the reactant tin, as long as the reaction took place in a closed system.

#"8.1 g"-"5.0 g"="3.1 g"#