Chemical Reactions, Matter and Energy

Which of the following is an example of a chemical change?

• water freezes to form ice

• sugar dissolves in water

• gasoline burns in a car engine

• a piece of metal expands when it is heated

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

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

• Physical

• Chemical

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

What is the Law of Conservation of Mass?

• It states that matter cannot be created or destroyed.

• It states that energy cannot be created or destroyed.

• It states that matter can be created or destroyed.

• It states that sound can be created or destroyed.

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Which of the following equations are correctly balanced?

• 12CO₂ +H₂O --> C₆H₁₂O₆ + O₂

• CO₂ + 9H₂O --> C₆H₁₂O₆ + O₂

• CO₂ + H₂O --> 3C₆H₁₂O₆ + O₂

• 6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Balance the following equation:

___ H₂+ ___ O₂→___ H₂O

• 1, 1, 3

• 2, 2, 2

• 1, 2, 1

• 2,1, 2

Tags

NGSS.MS-PS1-5

Balance the following equation:

___ Mg+ ___ O₂→___ MgO

• 1, 1, 3

• 2, 1, 2

• 1, 2, 1

• 2, 2, 2

Tags

NGSS.MS-PS1-5

Is the following equation balanced?

Al + O₂ ---> 2Al₂O₃

• YES

• NO

Tags

NGSS.MS-PS1-5

What is the number before a chemical formula called?

Example: 2H₂ + O₂ ---> 2H₂O

• Coefficient

• Atom

• Subscript

• Equation

Complete the sentence.

During a chemical reaction, atoms ________.

• can appear

• can disappear

• get rearranged

• stop moving and vibrating

Tags

NGSS.MS-PS1-5

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

• Reactants

• Products 

• Yields 

• Chemical Equation