Mrs. Bodan explains the law of conservation of mass, comparing open and closed systems through experiments. In a closed system, mass is conserved as gases are contained, while in an open system, gases escape, leading to a mass difference. The video demonstrates these concepts using vinegar and baking soda reactions, highlighting the importance of understanding system boundaries in chemical reactions.

What does the Law of Conservation of Mass state?

• Mass can be both created and destroyed in a chemical reaction.

• Mass cannot be created or destroyed in a chemical reaction.

• Mass can be destroyed in a chemical reaction.

• Mass can be created in a chemical reaction.

Tags

NGSS.MS-PS1-5

In an open system, what can leave the system?

• Only matter

• Only energy

• Both matter and energy

• Neither matter nor energy

What is used to seal the flask in the closed system experiment?

• A cork

• A plastic wrap

• A balloon

• A lid

Tags

NGSS.MS-ETS1-2

What was the initial mass in the closed system experiment?

• 234 grams

• 236 grams

• 240 grams

• 232 grams

What was the final mass in the closed system experiment?

• 240 grams

• 232 grams

• 236 grams

• 234 grams

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Why was there a difference in mass in the closed system experiment?

• The scale was faulty.

• The balloon was not sealed properly.

• Some mass was lost.

• Other forces were at work.

Tags

NGSS.MS-PS1-5

What was the initial mass of the flask and vinegar in the open system experiment?

• 482 grams

• 480 grams

• 486 grams

• 484 grams

What was the mass of the cup used to measure baking soda in the open system experiment?

• 2 grams

• 4 grams

• 6 grams

• 8 grams

What was the final mass after the open system experiment?

• 496 grams

• 502 grams

• 498 grams

• 500 grams

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

How much mass was lost to the surrounding air in the open system experiment?

• 5 grams

• 6 grams

• 4 grams

• 7 grams

Tags

NGSS.MS-PS1-5