Chemical Reactions

Which one shows that a chemical reaction has occurred?

• dissolving

• melting

• formation of a new gas

• dissolving

Tags

NGSS.MS-PS1-2

What is the BEST definition of a chemical reaction?

• A change in matter that produces one or more NEW substances

• When two things combine and EXPLODE.

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

• Mg and O
• MgO
• Mg and MgO
• O and MgO

Tags

NGSS.MS-PS1-2

A teacher is demonstrating physical and chemical changes to her class. Which action should she use to demonstrate a chemical change?

• cutting a piece of paper
• folding a piece of paper
• tearing a piece of paper
• burning a piece of paper

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

What are the products of the chemical reaction pictured?

• CH₄ and CO₂

• CH₄ and O₂

• CO₂ and 2 H₂O

• O₂ and H₂O

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Consider the chemical equation CH₄ + 2 O₂ → CO₂ + 2 H₂O. In this equation, CH₄ is a

• product
• reactant
• displacement

In a chemical reaction, the number of atoms in the reactants and the products...

• Must be the same

• Must be different

Tags

NGSS.MS-PS1-5

• 2

• 3

• 5

• 6

Tags

NGSS.MS-PS1-5

The Law of Conservation of Mass says that matter can neither be __________ or __________.

• created; destroyed

• recycled; renewed

• subtracted; added

• joined; separated

Tags

NGSS.MS-PS1-5

In a reaction A + B ----> C,  reactant A has 5g and product  C has 9g. How many grams does reactant B should have? 

• 4g
• 5g
• 9g
• 14g

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2