Science 10

Learning Intentions

• To learn how to represent chemical reactions using words
• To learn how to represent chemical reactions using chemical equations
• To learn how to balance chemical equations
  

Notes

If you have forgotten how to balance chemical equations, please review the Virtual Lab on Balancing Chemical Equations.

Sample Questions

For the following questions, please write out the balanced chemical equation for the reaction.

1. Copper metal reacts with silver nitrate, forming copper (I) nitrate and silver crystals.
   
   
   Cu + AgNO₃ → CuNO₃ + Ag
   
   
2. Magnesium metal reacts with sodium fluoride to produce magnesium fluoride and sodium metal.
   
   
   Mg + 2 NaF → MgF₂ + 2 Na
   
   

For the following equations, add coefficients to balance them, then write out a sentence describing the products and reactants of the chemical reaction.

1. ____ NaCl + ____ F₂ → ____ NaF + ____ Cl₂
   
   
   2 NaCl + F₂ → 2 NaF + Cl₂
   Sodium chloride (table salt) reacts with fluorine gas to form sodium fluoride and chlorine gas.
   
   
2. ____ N₂ + ____ H₂ → ____ NH₃
   
   
   N₂ + 3 H₂ → 2 NH₃
   Nitrogen gas reacts with hydrogen gas to form ammonia.
   

Homework Questions

Part 1

For the following questions, please write out the balanced chemical equation for the reaction.

1. Zinc metal reacts with lead (II) nitrate to form zinc nitrate and lead metal.
2. Sodium phosphate reacts with calcium chloride to form calcium phosphate and sodium chloride.
3. Lithium hydroxide reacts with sulfuric acid to form lithium sulfate and water.
4. Sugar (C6H12O6) burns in oxygen to form carbon dioxide and water vapour.
5. Potassium metal reacts with chlorine gas to form potassium chloride.
   
6. Aluminum bromide reacts with chlorine gas to form aluminum chloride and bromine gas.
7. Hydrogen gas burns in oxygen to form water vapour.
   
8. Copper reacts with sulfuric acid to form copper (II) sulfate, water, and sulfur dioxide.
   
9. Calcium hydroxide reacts with phosphoric acid to form calcium phosphate and water.
10. Hydrochloric acid reacts with calcium carbonate to form calcium chloride, water, and carbon dioxide gas.

Part 2

For the following equations, add coefficients to balance them, then write out a sentence describing the products and reactants of the chemical reaction.

1. ____ Pb(OH)₂ + ____ HCl → ____ H₂O + ____ PbCl₂
   
2. ____ CH₄ + ____ O₂ → ____ CO₂ + ____ H₂O
3. ____ C₈H₁₈ + ____ O₂ → ____ CO₂ + ____ H₂O
4. ____ P + ____ O₂ → ____P₂O₅
   
5. ____ Ag₂O → ____ Ag + ____ O₂
6. ____ S₈ + ____ O₂ → ____ SO₃
   
7. ____ CO₂ + ____ H₂O → ____ C₆H₁₂O₆ + ____ O₂
8. ____ HNO₃ + ____ NaHCO₃ → ____ NaNO₃ + ____ H₂O + ____ CO₂
9. ____ NaBr + ____ CaF₂ → ____ NaF + ____ CaBr₂
   
10. ____ H₂SO₄ + ____ NaNO₂ → ____ HNO₂ + ____ Na₂SO₄
    

Part 3

For each of the questions in part 1 and part 2, find the type of reaction (synthesis, decomposition, single replacement, double replacement, combustion, or other).