Chemical Reactions Quiz

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

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

To make elephant toothpaste, a catalyst (KI) is added to hydrogen peroxide (H₂O₂). The reaction creates a large amount of foam and liquid in the bottom of the bottle. Which of the following is a reactant in the formula?
2 H₂O₂ -> 2 H₂O + O₂

• H₂0
• KI
• H₂O₂
• O₂

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-1

Identify the reactant(s) and product(s) of the reaction.

• All three are reactants and none are products.
• Hydrogen and water are the reactants, and oxygen is the product.
• Water and oxygen are the reactants, and hydrogen is the product.
• Hydrogen and oxygen are the reactants, and water is the product.
  

What is the arrow in a chemical equation...
H_{2 +} O --> H₂O

• Reactants
• Products 
• Yields 
• Chemical Equation 

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5