The Reaction That Runs Backwards
📖 The Reaction That Runs Backwards
Reversible reactions are like a revolving door! People can go in (forward reaction) AND come out (backward reaction) through the same door. Both directions happen at the same time. The ⇌ symbol shows this two-way traffic. Just like a revolving door, both processes are happening constantly — it just looks still when the same number enter as leave!
Chemistry glossary
- What is a reversible reaction?
- A reaction where products can react together to reform the original reactants
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🧠 Memory Aid: Double Arrow = Two-Way Traffic
The ⇌ symbol is your key visual reminder:
- → = one-way street (irreversible reaction)
- ⇌ = two-way road (reversible reaction, traffic flows both ways)
For the energy rule, remember the phrase: "FORWARD EXO = BACKWARD ENDO" — if energy is released going forward, it must be absorbed going backward. Think of a ball rolling down a hill (exothermic forward) — you need to push it back up the same hill (endothermic backward), using exactly the same energy it released coming down.
For copper sulfate: Blue has water, White has none — heat makes it white, add water makes it blue.
Now try it yourself
Quiz · Question 1 of 20
What does the symbol ⇌ mean when used in a chemical equation?
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