Chemical Reactions Review

Which of the following is a sign that a chemical reaction has occurred?

• change in shape
• melting
• formation of a gas
• dissolving

Is melting butter for popcorn a chemical or physical change?

• chemical
• physical

A solid piece of chocolate is melted and changed to liquid form. Which property of the piece of chocolate will remain the same?

• Texture
• Temperature
  
• Shape
•  Mass

A change where one or more new substances are created.

• Physical Change 
• Chemical Change 

What kind of properties can only be observed when a substance changes into a different substance?

• physical properties
• chemical properties

What does the Law of Conservation of Mass state?

• Matter cannot be gained or lost in a chemical reaction.
• Matter can only be lost in a chemical reaction.
• Matter can only be gained in a chemical reaction.
• Matter can be gained and lost in a chemical reaction. 

What is the left part of a chemical equation called?
2H_{2 +} O₂ --> 2H₂O

• Reactants
• Products 
• Yields 
• Chemical Equation 

What is the right part of a chemical equation called...
2H_{2 +} O₂ --> 2H₂O

• Reactants
• Products 
• Yields 
• Chemical Equation 

Tags

NGSS.MS-PS1-5

What is the little number after an element in a chemical equation called.
Example: H₂

• Coefficient 
• Subscript
• Atom
• Equation

Is the following equation balanced?...
Al + O₂ --> 2Al₂O₃

• Yes!
• No!

Tags

NGSS.MS-PS1-5