Chemistry Science

Define Reactants

• the building block of matter
• a description of a reaction
• the substances produced in a reaction
• the starting substances in a chemical reaction

Which is a sign of a chemical reaction?

• chemical properties change
• a gas forms
• a solid forms
• physical properties change

Explain why subscripts cannot change when balancing a chemical equation

• Gives the amount of atoms
• You can change subscripts
• The identity of a substance changes
• None of the above

Define products

• The substance produced in a chemical reaction
• Another word for ions
• A description of a reaction
• Process in which atoms bond together

Which of these are signs that a chemical reaction has occurred?

• Change in color 
• Release of light
• Change in odor
• All are correct

What is a chemical reaction?

• produces or yields
• an attraction between atoms
• a process in which one or more substances rearrange to form a new one
• state that the identity stays the same before and after 

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

A chemical equation is a description of a reaction using symbols

• TRUE
• FALSE

Tags

NGSS.HS-PS1-7

Atoms separate, rearrange, and new bonds form in a chemical reaction

• FALSE
• TRUE

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The arrow in a chemical equation separates two or more reactants 

• FALSE
• TRUE

What is a coefficient?

• Number of protons of that substance in a reaction
• Number of electrons of that substance in the reaction
• Number of units of that substance in the reaction
• Number of metallic bonds