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⚗️ Interactive Chemistry Lab

Balancing
Chemical
Reactions

Master atomic conservation through interactive experiments, animations, and challenges.

10Slides
2Exercises
5Quiz Qs
O H H
H₂O — Water
Concept 01

What is a Chemical Reaction?

⚛️

Reactants

Starting substances on the left side of the equation.

A + B →

Products

New substances formed on the right side of the equation.

→ C + D
⚖️

Conservation

Atoms are never created or destroyed in a reaction.

In = Out
H
H
+
O
H₂O

Hydrogen + Oxygen → Water

Concept 02

Law of Conservation of Mass

"Matter is neither created nor destroyed in a chemical reaction."
— Antoine Lavoisier, 1789
FeFeOOO
Reactants
FeFeOOO
Products
2Fe + 3OFe₂O₃

Both sides: 2 Fe + 3 O atoms ✓

Method

How to Balance Equations

01

Write the Unbalanced Equation

Use correct chemical formulas for all reactants and products.

H₂ + O₂ → H₂O
02

Count Atoms on Each Side

Tally every element and identify imbalances.

H2vs2
O2vs1
03

Add Coefficients (Not Subscripts!)

Place numbers in front of formulas only — never change subscripts.

2H₂ + O₂ → 2H₂O
04

Verify Both Sides Match

Recount all atoms to confirm equality.

H4vs4
O2vs2
Animation

Watch: Forming Water

2H₂ + 1O₂ 2H₂O
H atoms:44
O atoms:22
Exercise 01

Balance: H₂ + O₂ → H₂O

1
H₂
+
1
O₂
1
H₂O
H2vs2⚠️
O2vs1
Exercise 02

Combustion of Methane

🔥

Methane (CH₄) burns in oxygen producing CO₂ and H₂O — how natural gas stoves work!

1
CH₄
+
1
O₂
1
CO₂
+
1
H₂O
C1vs1
H4vs2
O2vs3
Concept 03

Types of Chemical Reactions

Synthesis

A + B → AB
2H₂ + O₂ → 2H₂O
💥

Decomposition

AB → A + B
2H₂O → 2H₂ + O₂
🔥

Combustion

Fuel + O₂ → CO₂ + H₂O
CH₄ + 2O₂ → CO₂ + 2H₂O
🔄

Single Replacement

A + BC → AC + B
Zn + 2HCl → ZnCl₂ + H₂
🔀

Double Replacement

AB + CD → AD + CB
NaCl + AgNO₃ → NaNO₃ + AgCl
← Click a reaction type to learn more
Quiz Time!

Test Your Knowledge

Summary

Key Takeaways

⚖️
Conservation of Mass

Atoms are never created or destroyed.

🔢
Coefficients Only

Change numbers in front, never subscripts inside formulas.

📋
Count Every Atom

Tally each element on both sides systematically.

🔄
One Element at a Time

Save H and O for last when balancing.

Always Verify

Recount all atoms after balancing to confirm.

Quick Reference
SynthesisA + B → AB
DecompositionAB → A + B
CombustionFuel + O₂ → CO₂ + H₂O
Single Rep.A + BC → AC + B
Double Rep.AB + CD → AD + CB
Chemistry
Master!
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