Balancing Chemical Equations

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

What law governs the balancing of chemical equations? 

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

What is the Law of Conservation of Mass?

• It states that no matter can be created or destroyed.
• It states that no energy can be created or destroyed.
• It states that matter can be created or destroyed.
• It states that no sound can be created or destroyed.

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

• 1
• 2
• 3
• 4

Is this balanced?
Al + O₂ → 2Al₂O₃

• Yes
• No

Which number should go in the blank?
Al(NO₃)₃ + _  NaOH -> Al(OH)₃ + 3 NaNO₃

• 1
• 2
• 3
• 0

What coefficient should be used to make the following equation balanced?
N₂+O₂--> _NO 

• 1
• 2
• 3
• 4

Which problem is balanced?

• PbO₂ + 2H₂
• SO₂ + H₂0 --> H₂SO₄
• 2Na + 2H₂O --> 2NaOH + H₂

Balance this equation
_Zn+_HCl-->_ZnCl₂ +_H₂

• 1,1,2,1
• 1,1,1,2
• 1,2,1,1
• 2,1,1,1