Writing Balanced Chemical Equations
The full lesson can be viewed by enrolling in the Year 9 Chemistry Online Course or by purchasing the Year 9 Chemistry Lesson Notes.
Learning Objective
In this lesson we will learn how to write chemical equations in a way that reflects the Law of Conservation of Mass.
Learning Outcomes
By the end of this lesson you will be able to:
- Define the Law of Conservation of Mass.
- Explain how the Law of Conservation of Mass applies to chemical reactions.
- Write a balanced chemical equation.
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Lesson Summary
- The Law of Conservation of Mass states that matter is neither created nor destroyed.
- To reflect the conservation of mass in a chemical reaction, chemical equations need to be balanced.
- Equations are balanced by adding coefficients (numbers) in front of the chemical formulas of reactants and products.
- A balanced equation shows equal numbers of each type of atom on both sides of the equation.
- It reflects the ratios of each reactant and product involved in the reaction.
- Steps for writing a balanced chemical equation:
- Write the formula equation showing all reactants and products.
- Tally up the total numbers of each type of atom for both sides of the equation.
- Place coefficients in front of reactants and products until there are equal numbers of each type of atom on both sides of the equation.
Click image to preview the worksheet for this lesson.
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Click image to preview the Year 9 Chemistry Workbook (print version).
Click image to preview the Year 9 Chemistry Lesson Notes.