Balancing Chemical Equations
Grade 8 · Science · Chemistry · Nunavut, Canada
Lesson Summary
Make sure the same number of each atom appears on both sides of a chemical equation.
Explanation
In a chemical reaction, atoms are not created or destroyed—they are rearranged. A balanced equation has the same number of each type of atom on both sides of the arrow. You balance an equation by placing coefficients (numbers in front of formulas) to adjust the count of atoms. Never change the subscripts in a formula, because that would change the substance itself. Balancing equations is a core skill in chemistry that reflects the law of conservation of mass.
Practice Questions
Q1: Balance this equation: H₂ + O₂ → H₂O
Answer: 2H₂ + O₂ → 2H₂O. This gives 4 hydrogen atoms and 2 oxygen atoms on each side.
Q2: Why must chemical equations be balanced?
Answer: Because of the law of conservation of mass—atoms cannot be created or destroyed, so the same atoms must appear on both sides.
Q3: When balancing an equation, can you change the subscripts in a chemical formula?
Answer: No. Changing subscripts would change the substance itself. You can only add coefficients in front of formulas.
People Also Ask
What is Balancing Chemical Equations in Grade 8 Science?+
Balancing Chemical Equations is a lesson in the Chemistry chapter of Grade 8 Science. It is part of the Nunavut, Canada school curriculum and covers key concepts that students need to understand at this level.
What grade level covers Balancing Chemical Equations?+
Balancing Chemical Equations is taught in Grade 8 as part of the Science curriculum in Nunavut, Canada.
How can I help my child with Chemistry in Science?+
Start with the lesson summary and explanation on this page. Practice the questions provided, then use TutorTom for personalized, step-by-step help with Chemistry topics.