Balancing Chemical Equations

The substances that go into a reaction are called the _______.

• products

• reactants

An ENDOTHERMIC reaction would feel ______ to the touch, while an EXOTHERMIC reaction would feel ______ to the touch.

• hot ; cold

• cold ; hot

What is the number before a chemical formula called?

Example: 2H₂ + O₂ ---> 2H₂O

• Coefficient

• Atom

• Subscript

• Equation

What is the little number after an element in a chemical equation called?

Example: H₂

• Coefficient

• Atom

• Subscript

• Equation

Balance this equation

_Al +_HCl --> _H₂ +_AlCl₃

• 2,6,3,2

• it's already balanced

• 4,12,3,4

• 2,1,4,5

What are the coefficients that would properly balance this equation?

__AgNO₃ + __H₂S --> __Ag₂S+ __HNO₃

• 2,1 --> 1,2

• 1,2 --> 1,1

• 1,2 --> 1,2

• 1,2 --> 2,1

What are the coefficients that would properly balance this equation?

__H₂ + __S --> __H₂S

• 1,1 --> 1

• 2,2 --> 2

• 1,2 --> 1

• 1,2 --> 2

What are the coefficients that would properly balance this equation?

__Al + __O₂--> __Al₂O₃

• 4,1 --> 2

• 4,3 --> 4

• 3,4 --> 1

• 4,3 --> 2

Which number should go in the blank?
Mn + _ HNO₃ → Mn(NO₃)₂ + H₂

• 1
• 2
• 3
• 0

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

• 1
• 2
• 3
• 0