Law of Conservation of Mass

How many Ca (Calcium) atoms are found in Ca(OH)_2?

• 5 atoms

• 3 atoms

• 2 atoms

• 1 atom

Does this equation follow the Law of Conservation of Mass?

2Fe₂O₃ + 3C → 4Fe + 3 CO₂

• No, because there are more reactants than products.

• No, because there are more products than reactants.

• Yes, because the reactants equal the products.

• Yes, because the reactants do not equal the products.

How many atoms do you have in the chemical formula 3H₂O₂?

• 7 atoms

• 12 atoms

• 4 atoms

• 6 atoms

Does the equation H₂+O₂ →H₂O follow the Law of Conservation of Mass?

• Yes, because the atoms are equal.

• No, because more info is needed.

• No, because there are more atoms in the product.

• No, because there are more atoms in the reactant.

In a reaction A + B → C, reactant A has 5 g and product C has 9 g. How many grams does reactant B should have?

• 4 g

• 5 g

• 9 g

• 14 g

In this reaction, how much CO₂ is produced?

• 42 g

• 24 g

• 23 g

• No grams produced

Law of conservation of mass states the amounts of atoms in the reactants and the products...

• Increase

• Decrease

• Stay the same

• No correct answer

If there are 4 Hydrogen atoms on the reactant side, how many Hydrogen atoms will be on the product side?

• More information is needed to answer

• 6 atoms

• 4 atoms

• 2 atoms

If a reaction starts with a total 75 g of reactants it should produce

• a total of 40 g of products

• a total of 75 g of products

• a total of 180 g of products

• No correct answer

The Law of Conservation of Mass means that...

• The Mass of the reactants & products are equal.

• The Atoms of the reactants & products are equal.

• No mass or atoms is gained or lost during a chemical reaction.

• All the states are correct.