Chemical Reactions

When a magnesium ribbon is burnt in air, the ash formed is

• Black

• White

• yellow

• Pink

In a ___________change, a substance changes into a different substance.

• Physical
• Chemical

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of these is NOT a sign that a chemical change has occurred? 

• A loss of transparency 
• An unexpected color change
• A temperature change
• The formation of a precipitate

Tags

NGSS.MS-PS1-2

In a chemical reaction, bonds are broken and new bonds are formed that create new substances. The bonds that are broken are called what?

• Reactants
• Products
• Atoms
• Catalysts

Tags

NGSS.MS-PS1-2

The Law of Conservation of Mass states

• that matter exists in all states and reacts the same
• that matter can only be changed into new substances by introducing a catalyst
• that matter exists in the same state throughout any chemical change
• that matter cannot be created or destroyed and that the mass of the products must equal the mass of the reactants

Tags

NGSS.MS-PS1-5

How many Al atoms are in this compound?         4Al₂O₃

• 2
• 8
• 6
• 4

Tags

NGSS.MS-PS1-1

a copper penny turning greenish after a few years.

• Chemical Change
• Physical Change

Tags

NGSS.MS-PS1-2

An gel ice pack getting cold after you put it in the freezer for an hour.

• Chemical Change
• Physical Change

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which of the following IS a physical change?

• Getting a haircut
• Rusty metal
• sour milk
• A compound

___________________ are the elements are compounds that leave (are formed in) a chemical
reaction.

• Polymers
• Bonds
• Reactants
• Products

Tags

NGSS.MS-PS1-5