Law of Conservation of Mass Quiz

What is the Law of Conservation of Mass?

• Where atoms are added and removed to form a new substance.

• Where mass changes after a chemical reaction.

• Where mass is the same before and after a chemical reaction

• Where atoms are completely changed to form a new substance

What is the part of the chemical formula that tells us the substances that go into the chemical reaction?

• Product

• Yield

• Reactant

• Atoms in product

Chemical equations are written as

• products = reactants

• products + reactants

• reactants --> products

• reactants + products

What is the part of the chemical formula that tells us the results of chemical reaction?

• Product

• Yield

• Reactant

• Atoms in product

Each atom has _____________, therefore the mass should be the same before and after the chemical reaction.

• weight

• mass

• protons

• electrons

The ___________ number of atoms are in the reactant and the product.

• different

• same

• odd

• proton

When a chemical reaction occurs, atoms that make up the reactant are rearranged to form _____________ ___________ in the product.

• something else

• chemical reaction

• new substance

• same substance

The coefficient in 3H2O is ______

• 6

• 3

• 2

• 5

Do the equation represent the law of conservation of mass?

P₄ + 3O₂ ---> 2P₂O₃

• Yes

• No

Does this equation represent the law of conservation of mass?

2Mg + O₂ ---> 2MgO

• Yes

• No