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⚙️ Unit C4: Metals & Reactivity Series

Explore how metals react with oxygen, water, steam and acids — and their order of reactivity

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🏆 The Reactivity Series

🧠 Mnemonic: "Please Send Charlie's Monkeys And Zebras In Lead Cages Securely Guarded"

Please → Potassium (K)
Send → Sodium (Na)
Charlie's → Calcium (Ca)
Monkeys → Magnesium (Mg)
And → Aluminium (Al)
Zebras → Zinc (Zn)
In → Iron (Fe)
Lead → Lead (Pb)
Cages → Copper (Cu)
Securely → Silver (Ag)
Guarded → Gold (Au)

🔥 Reactivity Series (Most → Least Reactive)

↑ MOST REACTIVE
1
⚡ Potassium (K)
reacts violently with water
2
⚡ Sodium (Na)
reacts violently with water
3
🔵 Calcium (Ca)
reacts readily with water
4
🔵 Magnesium (Mg)
reacts slowly with water, fast with steam
5
🟡 Aluminium (Al)
protected by oxide layer
6
🟡 Zinc (Zn)
reacts with steam & dilute acids
7
🟠 Iron (Fe)
reacts slowly with dilute acids
8
🟠 Lead (Pb)
reaction with HCl stops due to PbCl₂ layer
9
🟢 Copper (Cu)
does not react with acids/water/steam
10
🟢 Silver (Ag)
very unreactive
11
🟢 Gold (Au)
very unreactive
↓ LEAST REACTIVE

🔥 Reactions of Metals with Oxygen

Most metals react with oxygen to form metal oxides:

Metal + Oxygen → Metal Oxide
MetalObservation with O₂ProductEquation
🔥 MagnesiumBurns with a BRIGHT white flameMagnesium oxide (white ash)2Mg + O₂ → 2MgO
🌡️ IronGlows RED when heatedIron(III) oxide4Fe + 3O₂ → 2Fe₂O₃
🔵 CopperDoes NOT burn or glow; turns black slowlyCopper(II) oxide (black)2Cu + O₂ → 2CuO
📊 Order (most → least reactive with O₂)
Magnesium > Iron > Copper

💧 Reactions of Metals with Water & Steam

Metal + Water → Metal Hydroxide + Hydrogen
MetalWith Cold WaterWith Steam
⚡ SodiumReacts VIOLENTLY — hisses, moves, ignites—
🔵 CalciumReacts READILY — many bubbles of H₂—
🟡 MagnesiumReacts VERY SLOWLY — few bubblesReacts VIGOROUSLY — MgO + H₂
🟢 CopperNO REACTIONNO REACTION

Key equations:

2Na + 2H₂O → 2NaOH + H₂
Ca + 2H₂O → Ca(OH)₂ + H₂
Mg + H₂O (steam) → MgO + H₂
💡 Why is sodium stored in paraffin oil?
Sodium reacts violently with water and oxygen in air. Paraffin oil keeps it away from moisture and air.

🧪 Reactions of Metals with Dilute Acids

Metal + Hydrochloric Acid → Metal Chloride + Hydrogen
MetalReaction with HClProducts
🔥 MagnesiumReacts VERY FAST — lots of bubblesMgCl₂ + H₂
🟡 ZincReacts MODERATELY FASTZnCl₂ + H₂
🟠 IronReacts SLOWLY — pale green solutionFeCl₂ + H₂
🟢 CopperNO REACTION—

Key equations:

Mg + 2HCl → MgCl₂ + H₂
Zn + 2HCl → ZnCl₂ + H₂
Fe + 2HCl → FeCl₂ + H₂
📊 Order (most → least reactive with HCl)
Magnesium > Zinc > Iron > Copper (no reaction)

🧠 Quiz Time! Chapter 4

Test what you've learnt! Pick the best answer.