Describing Chemical Reactions

Is ths a chemical or a physical change?

• Chemical change
• Physical change

Tags

NGSS.MS-PS1-2

Why is tearing a piece of paper only a physical change?

• It changes the paper. 
• It is hard to tear. 
• It only changes its size, but it's still paper
• None of the above

Is burning a campfire a chemical or physical change?

• Chemical
• Physical 

Tags

NGSS.MS-PS1-2

WHY is burning a campfire a chemical change? 

• It created a new substance with new properties
• It changes in size 
• There is a lot of smoke
• The logs get smaller 

Tags

NGSS.MS-PS1-2

This is an accurate model because...

• It is missing one more CO₂ in the model. 
• Only the reactant side has the correct models for the formulas of each molecule. 
• It has the correct number of molecules and atoms for both sides of the equation. 
• None of the above 

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

In this model, the reactants are...

• 2H₂O
• H₂O₂
• 2H₂
• O₂

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-2

NGSS.MS-PS1-5

In this model, the PRODUCTS are 

• 2KI and 2KNO₃
• 2KI and Pb(NO₃)₂
• PbI₂ and 2KI
• PbI₂ and 2KNO₃

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What does the ARROW mean in a chemical reaction?

• go
• equals
• yields
• stop

Tags

NGSS.MS-PS1-2

What is a PRECIPITATE?

• When it rains.
• When a solid forms after 2 liquids mix and react. 
• When a solid forms after steam is produced. 
• When a solid forms after a liquid freezes. 

Tags

NGSS.MS-PS1-2

Is ice freezing a physical or chemical change?

• physical
• chemical

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-4