8.5E - Law of Conservation of Mass

Front

What is the Law of Conservation of Mass?

Back

The Law of Conservation of Mass states that mass is neither created nor destroyed in a chemical reaction. The total mass of reactants equals the total mass of products.

Front

In the reaction 2H₂ + O₂ → 2H₂O, how much water is produced from 4g of H₂ and 32g of O₂?

Back

36g of H₂O is produced.

Front

If a student mixes 125 grams of sugar, 250 grams of water, and 5 grams of flavoring, what is the total weight of the solution?

Back

The total weight of the solution is 380 grams.

Front

How many grams of oxygen are needed to show conservation of mass in a reaction if 100g of reactants are used?

Back

7g of oxygen is needed.

Front

How many elements are present in the compound PbNO₃?

Back

There are 3 elements in PbNO₃: Lead (Pb), Nitrogen (N), and Oxygen (O).

Front

What happens to the total mass when ice melts in water?

Back

The total mass remains the same; if 200g of ice is added to 900g of water, the total mass is 1,100g.

Front

Define a reactant in a chemical reaction.

Back

A reactant is a substance that undergoes change during a chemical reaction.

Front

Define a product in a chemical reaction.

Back

A product is a substance that is formed as a result of a chemical reaction.

Front

What is a chemical equation?

Back

A chemical equation is a symbolic representation of a chemical reaction, showing the reactants and products.

Front

What does it mean for a reaction to be balanced?

Back

A balanced reaction has the same number of each type of atom on both sides of the equation, reflecting the Law of Conservation of Mass.