Chemical reactions

Describes the number of molecules in a compound and is used to balance a chemical reaction. 

• coefficient 
• subscript
• superscript
• SI unit

Tags

NGSS.MS-PS1-5

Which type of reaction takes place in the presence of oxygen and produces carbon dioxide and water?

• double replacement 
• decomposition 
• combustion 
• single replacement

Tags

NGSS.MS-PS1-2

A compound is reacted and forms two new substances. What type of reaction is this? 

• combustion 
• synthesis 
• decomposition 
• single replacement 

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Describes the number of atoms in a compound of each element. 

• coefficient 
• superscript 
• subscript 
• SI unit 

Tags

NGSS.MS-PS1-1

What are the correct coefficients when this equation is balanced?
KClO₃  --> KCl  +  O₂

• 2,2,2
• 2,2,3
• 1,2,3
• 3,3,3

Tags

NGSS.MS-PS1-5

In a chemical reaction, bonds are broken and new bonds are formed that create new substances. The bonds that are broken are called what?

• Reactants
• Products
• Atoms
• Catalysts

Tags

NGSS.MS-PS1-2

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

How many Al atoms are in this compound?         4Al₂O₃

• 2
• 8
• 6
• 4

Tags

NGSS.MS-PS1-1

How many F atoms are in this compound?
6MgF₂ 

• 2
• 6
• 8
• 12

Tags

NGSS.MS-PS1-1

True or False
In a chemical reaction, no new atoms are created, and no atoms are destroyed. 

• true
• false

Tags

NGSS.MS-PS1-5