Law of Conservation of Mass Lab Investigation

What are you expected to determine in this lab investigation? Select all that apply.

• Whether a physical or chemical change has occurred

• What evidence indicates a new substance has formed

• How atoms rearrange in chemical reactions

• Whether mass is conserved when atoms rearrange

• The boiling point of vinegar

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Identify the reactant(s) and product(s) in the chemical reaction, CO₂ + H₂O ---> H₂CO₃.

• ---->

• reactants

• H₂CO₃

• equals

• CO₂ + H₂O

• products

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-1

A ​ (a)   occurs when atoms found in the ​ (b)   rearrange to form new ​ (c)   (called the ​ (d)   )

• chemical reaction
• reactants
• molecules
• products
• atoms
• elements

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

NGSS.MS-PS1-1

Fill in the blank: The Law of Conservation of Mass states that mass is _______ during a chemical reaction.

• conserved

• destroyed

• created

• lost

Tags

NGSS.MS-PS1-5

According to the Law of Conservation of Mass, what happens to the total mass of substances during a chemical reaction?

• It increases

• It decreases

• It stays the same

• It doubles

Tags

NGSS.MS-PS1-5

In the reaction CH₄ + 2O₂ → CO₂ + 2H₂O, the mass of the products is equal to the mass of the reactants.

• True

• False

Tags

NGSS.MS-PS1-5

Compare your observations of the system before and after each reaction. Describe any difference in appearance, temperature, color, or formation of new substances.

• There were changes in appearance, temperature, and/or formation of new substances after each reaction.

• No changes are observed in the system after each reaction.

• Only temperature changes, but appearance and color remain the same after each reaction.

• The system always becomes colder and darker after each reaction.

Tags

NGSS.MS-PS1-2

Use your observations from the investigation, identify whether each reaction was a physical or a chemical change.

• Each reaction was a chemical change.

• Each reaction was a physical change.

• Some reactions were neither physical nor chemical changes.

• All reactions were both physical and chemical changes.

Tags

NGSS.MS-PS1-2

Using the Periodic Table of Elements and the evidence from the table above, state whether the equation below is balanced or unbalanced. Explain your reasoning.

Reaction 1: C₂H₄O₂ (aq) + NaHCO₃ (s) → CO₂ (g) + H₂O (l) + Na⁺(aq) + C₂H₃O₂ (s)

• Yes, the equation is balanced because the number of atoms of each element is the same on both sides.

• No, the equation is unbalanced because the number of hydrogen atoms is not equal on both sides.

• No, the equation is unbalanced because the number of sodium atoms is not equal on both sides.

• No, the equation is unbalanced because the number of carbon atoms is not equal on both sides.

Tags

NGSS.MS-PS1-5

Reaction 1: C₂H₄O₂ (aq) + NaHCO₃ (s) → CO₂ (g) + H₂O (l) + Na⁺(aq) + C₂H₃O₂ (s)

Using the Periodic Table of Elements and evidence, compare the atoms on the reactant and the product side of the equation. The atoms on the reactant and product sides were:

• Rearranged, indicating a chemical reaction occurred.

• Unchanged, showing no reaction took place.

• Destroyed, meaning the elements disappeared.

• Created, meaning new elements formed.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2