3.1 Law of Conservation of Mass HW

Front

What is the Law of Conservation of Mass?

Back

The Law of Conservation of Mass states that in a closed system, the mass of the reactants before a chemical reaction is equal to the mass of the products after the reaction.

Front

What does a closed system mean in chemistry?

Back

A closed system is one where matter cannot enter or leave, but energy can be exchanged with the surroundings.

Front

What does an open system mean in chemistry?

Back

An open system is one where both matter and energy can flow freely in and out.

Front

In a chemical reaction, if the reactants weigh 50 grams, what will the products weigh?

Back

50 grams, according to the Law of Conservation of Mass.

Front

If 25 grams of salt is dissolved in 1,000 grams of water, what is the total mass of the solution?

Back

1,025 grams.

Front

What happens to the mass of reactants during a chemical reaction?

Back

The mass of the reactants remains the same as the mass of the products after the reaction.

Front

In the reaction AB -> A + B, if AB has a mass of 12g and B has a mass of 5g, what is the mass of A?

Back

7 grams.

Front

What is a reactant in a chemical reaction?

Back

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

Front

What is 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 an example of a physical change?

Back

Dissolving salt in water is a physical change, as the salt can be recovered.