Balancing Chemical Equations

In chemical reactions, what does the principle of conservation of mass mean?

• Matter is not created or destroyed.
• The total mass of the reactants is greater than the total mass of the products.
• The total mass of the reactants is less than the total mass of the products.
• Matter is not changed.
  

Which side of a chemical equation is the reactant side?

• Left (before the yields sign)
• Right (after the yields sign)

What is the right part of a chemical equation called...

H_{2 +} O₂ --> H₂O

• Reactants

• Products

• Yields

• Chemical Equation

Number of C's in 2Na₂CO₃

• 1
• 2
• 3
• 5

How many atoms of H in NH₄OH?

• 4

• 1

• 5

• 3

How many atoms of Ca in Ca(OH)₂?

• 1

• 2

• 3

• 0

How many atoms of H in Ca(OH)₂?

• 1

• 2

• 3

• 0

How many atoms of C in 2C₂H₆?

• 2

• 1

• 4

• 12

How many total atoms are in the compound C₂H₈O ?

• 11
• 2
• 8
• 1

Is the following equation balanced or unbalanced ? 
Al + O₂ --> Al₂O₃

• Balanced
• Unbalanced