Law of Conservation of Mass

Front

The law of conservation of mass states that matter cannot be created nor _________________.

Back

destroyed

Front

In a closed system, a chemical reaction takes place. The mass of the reactants in the beginning of the reaction is 25g. What does the mass have to be in the end of the reaction in order to follow the law of conservation of mass?

Back

25g

Front

The following chemical reaction occurs:
2S + 3O₂ -> 2SO_{3
How many atoms of oxygen are there in the reactant?}

Back

6 atoms of oxygen

Front

Mass of product: 30g, Mass of first reactant: 17g. What is the mass of the second reactant according to the law of conservation of mass?

Back

13g

Front

What evidence shows that the number of atoms before a chemical reaction equals the number after? Options: The mass of the plastic bag, baking soda, and vinegar before the reaction was equal to the mass after the reaction. Bubbles were produced during the reaction, which meant that a gas was being produced. The plastic bag did not change in any way, indicating that it was not involved in the reaction. The mass of the baking soda was exactly equal to the mass of the vinegar used to create the chemical reaction.

Back

The mass of the plastic bag, baking soda, and vinegar before the reaction was equal to the mass after the reaction.

Front

In a reaction A + B ----> C, reactant A has 5g and product C has 9g. How many grams does reactant B have? Options: 4g, 5g, 9g, 14g

Back

4g

Front

If reaction starts with 20g of reactants, what is the total mass of products produced?

Back

a total of 20g of products

Front

Ca + O₂ --> CaO
What coefficient goes in front of CaO?

Back

2

Front

Is this equation balanced?

Back

no

Front

Is this equation balanced?

Back

yes