Chemical Change and Law of Conservation of Mass

In any chemical reaction, the total amount of matter before the reaction and the total amount of matter after the reaction must STAY THE SAME according to:

• The Law of Equality

• The Law of Conservation of Energy

• The Law of Balance

• The Law of Conservation of Mass

Tags

NGSS.MS-PS1-5

How does a balanced chemical equation satisfy the Law of Conservation of Mass?

• During a chemical reaction, matter is destroyed

• During a chemical reaction, one or more new substances are formed

• During a chemical reaction, the total number of atoms increases

• During a chemical reaction, the total amount of matter stays the same

Tags

NGSS.MS-PS1-5

Which BEST explains why the total mass of the product(s) would be LESS than the total mass of the reactant(s) after a chemical reaction?

• Gases were released into the air during the reaction

• Precipitates were created during the reaction

• Atoms involved in the reaction lost mass

• A physical change has occurred

Tags

NGSS.MS-PS1-5

Plants create food by the process of photosynthesis. In this reaction, the plant starts with 6 atoms of carbon. In order for the matter to be conserved and the chemical reaction to stay balanced, how many atoms of carbon should be present AFTER this reaction?

• 2 atoms of carbon

• 3 atoms of carbon

• 6 atoms of carbon

• 12 atoms of carbon

Tags

NGSS.MS-LS1-6

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What is wrong with the reaction above?

• It does not create anything new

• It is not balanced properly

• It has no products

• It has no reactants

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of the following is responsible for a chemical change?

• cooling down

• crushing

• a chemical reaction

• melting

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What are the reactants of the reaction?

• CO₂ and O₂

• C₆H₁₂O₆ and H₂O

• C₆H₁₂O₆ and O₂

• CO₂ and H₂O

Tags

NGSS.MS-LS1-6

NGSS.MS-LS1-7

How are reactants and products different from one another?

• Products are the ingredients that go into a reaction; reactants are the results that come out

• Reactants and products are the same

• Reactants are the ingredients that go into a reaction; products are the results that come out

• There is no such thing as reactants and products

Tags

NGSS.MS-PS1-1

Which of the following is a sign that a chemical change or a chemical reaction has taken place?

• A liquid substance takes the form of its container

• The substance boils while being heated

• The substance condenses when cooled

• Bubbles form of a new gas being released

Tags

NGSS.MS-PS1-2

Which of the following chemical equations is balanced correctly?

• _{3H2 + O}2 -----> 2H₂O

• 2H₂ + O₂ ----> 2H₂O

• 2H₂ + 2O₂ ----> H₂O

• H₂ + O₂ ----> H₂O

Tags

NGSS.MS-PS1-5