Balancing Chemical Equations

How many Oxygens are in this molecule? 
(OH)₂

• 4
• 1
• 2
• 3

Tags

NGSS.MS-PS1-1

What are the smaller numbers that you CANNOT change in a chemical equation? 

• Coefficient
• Products
• Reactants
• Subscript

What are the larger numbers that you CAN CHANGE in a chemical equation? 

• Coefficient 
• Products
• Reactants
• Subscripts

How many HCl molecules do you need to balance this equation? 
Mg +  __HCl --->  MgCl₂ + H₂

• 1
• 2
• 3
• 4

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

Pb(NO₃)₂  +  KI --> PbI₂ + KNO₃
What type of reaction is this? 

• Synthesis 
• Decomposition 
• Single Replacement
• Double Replacement 

__Na  +  O₂ ----->  __Na₂O
Type of reaction? 
Balance it too. :)

• Synthesis, 2Na /  4Na₂O
• Decomposition, 4Na /  2Na₂O
• Synthesis, 4Na /  2Na₂O
• Decomposition, 2Na /  4Na₂O

Tags

NGSS.MS-PS1-5

NGSS.MS-PS1-2

What type of reaction is this?  
__H₂O₂ ---->  __H₂O + O₂

• Synthesis
• Decomposition 
• Single Replacement
• Combustion 

Tags

NGSS.MS-PS1-2

What law governs the balancing of chemical equations? 

• Law of Energy
• Law of Conservation of Matter/Mass
• Law of Gravity
• Law of Matter Movement 

Tags

NGSS.MS-PS1-5

Balance this chemical reaction......?  
__H₂O₂ ---->  __H₂O + O₂

• 2H₂O_{2  //}  2H₂O
• 1H₂O_{2  //}  2H₂O
• 2H₂O_{2  //}  1H₂O
• H₂O_{2  //}  2H₂O

Tags

NGSS.MS-PS1-5

Why is it called the Law of Conservation of Matter/Mass? 

• Energy is created and destroyed 
• Energy is never created, nor destroyed-- it always moves 
• Energy moves between particles
• Energy stops moving at the end of the universe 

Tags

NGSS.MS-PS1-5