Conservation of Mass - Lesson

Multiple Choice

24 g of magnesium reacts with 38 g of fluorine to produce ______ g of magnesium fluoride

• 14

• 24

• 38

• 62

Multiple Choice

12.67 g of Carbon reacts with 25.33 g of oxygen to produce ______ g of Carbon Dioxide

• 14

• 24

• 38

• 62

Multiple Choice

A company is designing a fuel that will burn efficiently while following the Law of Conservation of Mass. What must their design ensure?

• The mass of fuel burned must be greater than the mass of the exhaust gases.

• The atoms in the fuel must be completely destroyed in combustion.

• The total mass of reactants and products must be equal.

• The reaction must produce more mass than it started with.

Multiple Choice

Which statement best describes what happens during. a chemical reaction when two different substances form a new substance?

• Some of the atoms are destroyed and replaced by new atoms.

• All of the atoms are destroyed and all new atoms form.

• None of the atoms are destroyed but some new atom are added.

• None of the atoms are destroyed and no new atoms form.

Multiple Choice

Why does this picture demonstrate the Law of Conservation of Mass?

• the number of atoms of each element are the same on both sides

• they start out separate and end up combined

• the same elements are used

• it doesn't demonstrate the Law of Conservation of Mass

Multiple Choice

Which statement best describes how atoms rearrange in a chemical reaction?

• Some atoms disappear while new ones are created.

• The number of atoms in the reactants is different from the products.

• Atoms are rearranged into different compounds, but none are lost or gained.

• The reaction creates more mass than it started with.

Multiple Choice

The Law of Conservation of Mass says that matter can neither be __________ or __________.

• created; destroyed

• recycled; renewed

• subtracted; added

• joined; separated

Multiple Choice

How many sulfur atoms must be present in the products after a reaction between the following reactants: $$2SO_2\ +2H_2O_2$$  

• 2

• 3

• 4

• 8

Multiple Choice

How many Oxygen atoms must be present in the products after a reaction between the following reactants: $$2SO_2\ +2H_2O_2$$  

• 2

• 3

• 4

• 8

Multiple Choice

Does the image represent the Law of Conservation of

• yes

• no

Multiple Choice

A student places some baking soda and a jar of lemon juice in a plastic bag and seals the bag. They weigh the bag and everything in it. They shake the bag so that the lemon juice spills out of the jar and mixes with the baking soda inside the bag. The student observes that bubbles form and the bag expands. If the student weighs the bag and everything in it after the bubbling stops and compares the final weight to the starting weight, what will they find out?

• The final weight will be greater than the starting weight because new atoms are produced during the experiment.

• The final weight will be less than the starting weight because some of the atoms are destroyed during the experiment.

• The final weight will be the same as the starting weight because the number of each kind of atom does not change during the experiment.

• The final weight will be the same as the starting weight because some atoms are destroyed, but new ones are created during the experiment.

Multiple Choice

______ g of potassium reacts with 16 g of oxygen to produce 94 g of potassium oxide.

• 88

• 110

• 50

• 78

Multiple Choice

14 g of lithium reacts with _____ g of sulfur to produce 46 g of lithium sulfide.

• 32

• 60

• 25

• 10