Units / Unit A / Word Equations and Balancing (Conservation of Mass)

Word Equations and Balancing (Conservation of Mass)

Word ↔ balanced equations; Lavoisier conservation (A-GO3-SO6, SO1).

Full lesson guide (printable)

Outcome checklist

Alberta Program of Studies — tick each row when you can explain it without the slide.

A-GO3-SO6
By the end of this lesson you should be able to: Translate word equations to balanced chemical equations and vice versa for chemical reactions that occur in living and nonliving systems
Self-check: Without looking at your notes, give one example or explanation that shows you meet A-GO3-SO6.
A-GO3-SO1
By the end of this lesson you should be able to: Provide examples of household, commercial and industrial processes that use chemical reactions to produce useful substances and energy (e.g., baking powder in baking, combustion of fuels, electrolysis of water into H2(g) and O2(g))
Self-check: Without looking at your notes, give one example or explanation that shows you meet A-GO3-SO1.
A-GO3
Big idea: Identify and classify chemical changes, and write word and balanced chemical equations for significant chemical reactions, as applications of Lavoisier's law of conservation of mass
Self-check: How does today's lesson connect to A-GO3?

Where this shows up later

Unit A — Mole concept: Balanced equations enable mole ratios.

Glossary

reactant: Key vocabulary for this lesson (reactant). Use your class notes and the slide explanations to state it in your own words — Alberta Science 10 expects you to use this term correctly in context.
product: Key vocabulary for this lesson (product). Use your class notes and the slide explanations to state it in your own words — Alberta Science 10 expects you to use this term correctly in context.
coefficient: Key vocabulary for this lesson (coefficient). Use your class notes and the slide explanations to state it in your own words — Alberta Science 10 expects you to use this term correctly in context.
subscript: Key vocabulary for this lesson (subscript). Use your class notes and the slide explanations to state it in your own words — Alberta Science 10 expects you to use this term correctly in context.
conservation of mass: In a closed system, total mass before and after a change stays the same (Lavoisier).

Lab and demo watch-outs

Lab conservation demo
Follow school lab procedures and WHMIS labels for any chemicals shown.
Whenever chemicals or equipment are used in class.

Slide 1 of 911%

Hook

Lavoisier and the balance

Closed system mass before = mass after (within measurement).
Law of conservation of mass.

Core explanation

We start with a real situation: Closed system mass before = mass after (within measurement). Law of conservation of mass. Your job is to notice evidence and ask questions before memorizing definitions.

Check your understanding

Can you connect this slide to something we learned earlier today?

Explain moreDeeper teaching notes — read like a tutor explaining the idea

Unit A — Word Equations and Balancing (Conservation of Mass): Equations are sentences for reactions — balancing conserves atoms of each element. On this slide («Lavoisier and the balance»), the science story is: Closed system mass before = mass after (within measurement). Law of conservation of mass. Read like a tutor: connect each bullet to evidence or a model, not memorized wording. Alberta Science 10 expects you to explain ideas in class discussions and written work — this slide supports outcomes A-GO3-SO6, A-GO3-SO1.

Worked example(s)Step-by-step reasoning, not just answers

Apply: Lavoisier and the balance
1. State the core idea: Closed system mass before = mass after (within measurement).
2. Link to a second point: Law of conservation of mass.
3. Give one Alberta or daily-life example that fits both ideas.
4. Check your example against the slide — would your teacher agree?
Why this works: Application proves understanding beyond repeating bullets.

Common mistakes to avoid

Change subscripts to balance.
On «Lavoisier and the balance», use the slide model and vocabulary (reactant, product, coefficient, subscript) to replace this idea.

Try it yourself

Teach «Lavoisier and the balance» aloud in 60 seconds using two bullets and one vocabulary word from reactant.