A catalyst is a substance that speeds up a chemical reaction without being used up in the reaction.
📌 It lowers the activation energy, which makes the reaction happen faster or more easily.
🔹 Catalysts do not become part of the final product — they help but don’t get changed permanently.
🧪 Real-Life Example
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In your body, enzymes act as biological catalysts — they help digest food faster.
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In cars, catalytic converters use catalysts to reduce harmful gas emissions.
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In industry, iron is used as a catalyst to make ammonia (in the Haber process).
🔁 How Does a Catalyst Work?
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Every chemical reaction needs activation energy (energy to get started).
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A catalyst provides an easier path with lower energy.
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So the same reaction happens quicker and often at lower temperatures.
🧬 Types of Catalysts
| Type | Description | Example |
|---|---|---|
| Biological catalysts | Called enzymes, work in living cells | Amylase (digests starch) |
| Homogeneous catalyst | Same phase as reactants (e.g., all liquids) | Acid in esterification reaction |
| Heterogeneous catalyst | Different phase (e.g., solid in liquid) | Iron in ammonia production |
| Auto-catalyst | Product of reaction acts as its own catalyst | Manganese in some oxidation |
🧩 Key Characteristics of a Catalyst
✅ Speeds up reaction
✅ Not consumed in the reaction
✅ Used in small amounts
✅ Does not affect the amount of product
✅ Specific — works for certain reactions only
🧠 Fun Facts
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Catalysts are reused over and over again
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Without enzymes (natural catalysts), life processes would be too slow to support life
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Catalysis is used in over 90% of industrial chemical reactions
🧪 Catalyst vs. Reactant
| Feature | Catalyst | Reactant |
|---|---|---|
| Used up? | ❌ No | ✅ Yes |
| Affects speed? | ✅ Yes (faster) | ✅ Yes |
| Appears in product? | ❌ No | ✅ Yes |