Exploring the Law of Conservation of Mass

What is the main idea behind the Law of Conservation of Mass?

• Mass is always conserved and cannot be created or destroyed.

• Mass can be transferred from one object to another.

• Mass can be created or destroyed during a chemical reaction.

• Energy can be converted into mass.

Tags

NGSS.MS-PS1-5

In the first experiment, why is it important to use a crucible with a loose-fitting lid?

• To prevent the magnesium from escaping.

• To allow oxygen to enter and complete the reaction.

• To keep the magnesium oxide from reacting further.

• To ensure the magnesium does not melt.

Tags

NGSS.MS-PS1-2

Why do we need to record the mass of the crucible and magnesium strip before starting the experiment?

• To measure the amount of oxygen used.

• To compare the mass before and after the reaction.

• To check the temperature of the crucible.

• To ensure the magnesium is pure.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What indicates that a reaction is happening in the second experiment with calcium carbonate and hydrochloric acid?

• The mass of the flask increases.

• The temperature of the flask increases.

• The solution changes color.

• Bubbles form, indicating gas release.

Tags

NGSS.MS-PS1-2

What is the final mass recorded after the reaction between calcium carbonate and hydrochloric acid?

• 91.86g

• 80.13g

• 80.60g

• 48.36g

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What does a positive change in mass indicate in the results table?

• No change in mass.

• An increase in mass.

• A decrease in mass.

• A loss of reactants.

Tags

NGSS.MS-PS1-5

Why did the mass decrease in the reaction between calcium carbonate and hydrochloric acid?

• Some of the reactants were lost.

• The reaction was incomplete.

• A gas was released in an open system.

• The reactants dissolved completely.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What is the purpose of conducting the second experiment in a closed system?

• To ensure no gas escapes and mass is conserved.

• To prevent the reactants from mixing.

• To measure the temperature change.

• To increase the reaction rate.

Tags

NGSS.MS-PS1-5

What does the increase in mass in the magnesium and oxygen reaction represent?

• The amount of magnesium used.

• The loss of magnesium oxide.

• The temperature change during the reaction.

• The amount of oxygen combined with magnesium.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What is the main takeaway from the experiments regarding the Law of Conservation of Mass?

• Mass can be created in a closed system.

• Mass is always conserved, even if it appears to change.

• Mass can be destroyed in an open system.

• Mass is only conserved in solid reactions.

Tags

NGSS.MS-PS1-5