Law of Conservation of Matter

Manny poured 150 milliliters of water into a beaker. He found that the mass of the water was 150 grams. Then, Manny added 20 grams of soil to the water. He stirred until all of the soil was mixed into the water. What was the mass of the mixture?

• 20g

• 150g

• 170g

• 250g

Tags

NGSS.MS-PS1-5

Kayleigh mixes 40 grams of pebbles with 20 grams of sand. She makes this model to show the relationship of the individual substances and the mixture. Which statement BEST explains why the model is correct?

• It shows that there is more sand than pebbles.

• It shows that the mixture has an equal amount of sand and pebbles.

• It shows that sand is lost in making the sand and pebble mixture.

• It shows that matter from the substances is conserved in the mixture.

Charles makes three mixtures of milk and peanut butter. He puts a lid on each container and freezes each mixture. Some of his measurements are listed.

Container 1: 10 grams milk, 11 grams total mass, 11 grams frozen mass

Container 2: 20 grams milk, 21 grams total mass, 21 grams frozen mass

Container 3: 30 grams milk, 31 grams total mass, 31 grams frozen mass

Select THREE statements that describe patterns observed for the mixtures.

• The mass of the mixtures does not change in the freezer.

• Charles added the same amount of milk to each container.

• The total mass is the sum of all the ingredients for each mixture.

• Charles added the same amount of peanut butter to each container.

• The mass of the peanut butter changed in each container mixture.

Jenna has a container with 200 milliliters of juice. She adds 50 grams of sugar to the juice and stirs until it dissolves completely. What is the total mass of the juice mixture?

• 200g

• 250g

• 150g

• 300g

Tags

NGSS.MS-PS1-5

Alex combines 100 grams of salt with 200 grams of water. He claims that the mass of the mixture is less than the sum of the individual masses. Which statement BEST explains why his claim is incorrect?

• The salt dissolves completely, so its mass is not counted.

• The mass of the mixture is equal to the sum of the individual masses.

• The water evaporates, reducing the total mass.

• The salt and water chemically react to form a new substance.

Sam mixes 30 grams of sugar with 70 grams of flour. He creates a model to show the relationship between the substances and the mixture. Which statement BEST describes the model?

• It shows that the mixture has more sugar than flour.

• It shows that the mixture has more flour than sugar.

• It shows that sugar is lost in making the mixture.

• It shows that the total mass of the mixture is conserved.

Tags

NGSS.MS-PS1-5

What is matter?

• everything that has mass and occupies space

• something important

• only things that are heavy.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS1-1

True or False:

When water changes from solid to liquid state, some of the matter is destroyed

• True

• False

Tags

NGSS.MS-PS1-4

What happens to the mass of materials before and after an experiment?

• The mass remains the same.

• The mass decreases.

• The mass increases.

• The mass becomes null.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

100 grams of ice melt.

What is the mass of the melted ice?

• 75 grams

• 50 grams

• 100 grams

• 150 grams