MP Board Class 10 Science Chapter 3: Metals & Non-Metals Notes 2027 — Properties, Reactivity Series, Extraction & PYQs

Chapter 3: Metals & Non-Metals is one of the most important chapters in MP Board Class 10 Science, carrying 8–12 marks in the annual board exam. This chapter covers the physical and chemical properties of metals and non-metals, the reactivity series, extraction of metals from ores (metallurgy), and corrosion — its causes, prevention, and economic impact. Questions range from 1-mark MCQs to 5-mark detailed explanations with balanced equations. Mastering this chapter is essential for both board exams and competitive foundation exams.

⚙️ Physical Properties — Metals vs Non-Metals

Metals and non-metals have distinctly different physical properties. Understanding these differences helps in classifying elements and predicting their behaviour in chemical reactions.

📊 Comparison Table: Metals vs Non-Metals

🔑 Key Physical Properties in Detail

1. Malleability

Malleability is the property of metals to be beaten into thin sheets. This is possible because metals have layers of atoms that can slide over one another without breaking the metallic bond.

• Gold (Au) is the most malleable metal — can be beaten into sheets as thin as 0.0001 mm (gold leaf).
• Aluminium (Al) is used to make aluminium foil for food packaging.
• Silver (Ag) and Copper (Cu) are also highly malleable.

2. Ductility

Ductility is the property of metals to be drawn into thin wires. This occurs because metal atoms can rearrange along the length of the wire without breaking.

• Gold (Au) is the most ductile metal — 1 gram of gold can be drawn into a wire up to 2 km long.
• Copper (Cu) is widely used for electrical wiring due to its high ductility and conductivity.
• Aluminium (Al) wires are used for power transmission lines.

3. Electrical Conductivity

Metals conduct electricity due to the presence of free (mobile) electrons in their crystal lattice. These electrons can move freely through the metal and carry electric current.

• Silver (Ag) is the best conductor of electricity, followed by Copper (Cu) and Gold (Au).
• Copper is most commonly used for electrical wiring due to its good conductivity and lower cost.
• Graphite (a non-metal) can conduct electricity due to delocalised electrons in its layered structure.

4. Thermal Conductivity

Metals are good conductors of heat because free electrons transfer thermal energy rapidly through the metal. Cooking utensils are made of metals (Cu, Al, steel) because they conduct heat efficiently.

🧪 Chemical Properties

The chemical properties of metals and non-metals determine how they react with common substances like oxygen, water, acids, and bases. These reactions are the basis for understanding the reactivity series and extraction methods.

🔥 Reaction with Oxygen (Formation of Oxides)

Metals react with oxygen to form metal oxides. Most metal oxides are basic in nature — they react with water to form bases, or with acids to form salt and water.

⚗️ Metals + Oxygen → Metal Oxide

Different metals react with oxygen at different rates:

• Sodium (Na) and Potassium (K) react so vigorously with oxygen that they catch fire spontaneously in air. They are stored under kerosene to prevent contact.
• Magnesium (Mg) burns with a brilliant white flame to form MgO (magnesium oxide).
• Aluminium (Al) forms a thin, protective layer of Al₂O₃ on its surface that prevents further corrosion.
• Iron (Fe) burns only when heated strongly. Iron filings burn more readily.
• Copper (Cu) does not burn but slowly forms a black coating of CuO on heating.
• Gold (Au) and Platinum (Pt) do not react with oxygen at all — they are the least reactive.

🧪 Nature of Metal Oxides

Most metal oxides are basic — they turn red litmus blue and react with acids to form salt and water:

Some metal oxides like Al₂O₃ and ZnO are amphoteric — they react with both acids and bases:

⚗️ Non-Metals + Oxygen → Non-Metal Oxide

Non-metal oxides are acidic in nature — they turn blue litmus red and react with bases to form salt and water:

💧 Reaction with Water

Metals react with water to produce metal hydroxide and hydrogen gas. The vigour of the reaction depends on the reactivity of the metal.

📋 Reactivity of Metals with Water

Non-metals generally do not react with water. However, some non-metals like carbon react with steam: C + H₂O → CO + H₂ (water gas reaction, only at high temperatures).

🧪 Reaction with Acids

Metals react with dilute acids (HCl, H₂SO₄) to produce salt and hydrogen gas.

🔑 Key Observations

• The vigour of the reaction depends on the reactivity of the metal.
• Highly reactive metals (Na, K) react explosively — these are NOT tested with acids in the lab for safety.
• Moderately reactive metals (Zn, Fe, Mg, Al) react readily with dilute acids.
• Less reactive metals (Cu, Ag, Au) do NOT react with dilute acids.
• The H₂ gas produced can be tested by the pop test — a burning matchstick near the gas produces a pop sound.
• Nitric acid (HNO₃) is NOT used because it is a strong oxidizing agent and produces oxides of nitrogen instead of H₂.

❌ Reaction of Non-Metals with Acids

Non-metals generally do NOT react with dilute acids to produce hydrogen gas. This is because non-metals cannot displace hydrogen from acids.

🧪 Reaction with Bases

Some metals react with strong bases (alkalis like NaOH, KOH) to produce hydrogen gas. This property is limited to amphoteric metals like Zn and Al.

Non-metals like silicon can also react with bases: Si + 2NaOH + H₂O → Na₂SiO₃ + 2H₂↑ (Sodium silicate).

📊 Chemical Properties Summary Table

📊 Reactivity Series of Metals

The reactivity series (also called the activity series) is a list of metals arranged in order of decreasing reactivity. The most reactive metal is at the top, and the least reactive is at the bottom. This series is fundamental to understanding displacement reactions, extraction methods, and corrosion.

🔺 Reactivity Series (Top to Bottom)

🔑 Reactivity Series — Mnemonic

⚡ Displacement Reactions Based on Reactivity

Displacement reaction: A more reactive metal displaces a less reactive metal from its salt solution. This principle is used in many applications and is a very common exam question.

Observation: When iron is placed in blue copper sulphate solution —

• The blue colour of CuSO₄ solution fades gradually.
• A reddish-brown coating of copper is deposited on the iron nail.
• This is because Fe is more reactive than Cu and displaces it.

🔬 The Reactivity Series — Why it Matters

• Displacement Reactions: Predict whether one metal can displace another from its salt solution.
• Extraction of Metals: Determines the method used to extract a metal from its ore.
• Corrosion: More reactive metals corrode more easily.
• Electrochemical Series: Basis for Galvanic cells and batteries.

⛏️ Extraction of Metals (Metallurgy)

Metallurgy is the process of extracting metals from their ores and refining them for use. The method of extraction depends on the position of the metal in the reactivity series.

🏭 Step-by-Step Process: Ore to Pure Metal

Step 1: Mining → Crushing → Concentration (Enrichment of Ore)

The ore obtained from the earth’s crust contains impurities like sand, clay, and rocks (called gangue). The ore must be concentrated to remove gangue before further processing.

• Gangue: The unwanted earthy impurities (sand, clay, rock particles) present in the ore.
• Concentration: The process of removing gangue from the ore to increase the percentage of metal in the ore.

Methods of Concentration

Step 2: Conversion of Concentrated Ore into Metal Oxide

The concentrated ore is converted into its oxide form, which is then reduced to the metal. This is done by either roasting (for sulphide ores) or calcination (for carbonate/hydroxide ores).

Step 3: Reduction of Metal Oxide to Metal

The metal oxide is reduced to the free metal. The method depends on the reactivity of the metal:

A. Reduction by Carbon (Smelting) — for moderately reactive metals

Metals like Zn, Fe, Pb, Sn are extracted by heating their oxides with carbon (coke). Carbon acts as a reducing agent, removing oxygen from the metal oxide.

Blast Furnace for Iron: Iron is extracted from haematite (Fe₂O₃) using carbon monoxide as the reducing agent. The blast furnace operates at ~1900°C and produces molten iron (pig iron).

B. Reduction by Electrolysis — for highly reactive metals

Metals that are highly reactive (K, Na, Ca, Mg, Al) cannot be reduced by carbon because they have a strong affinity for oxygen. They are extracted by electrolytic reduction — passing electricity through their molten (fused) compounds.

C. Reduction by Aluminium (Thermite Process) — for high melting metals

Aluminium is a strong reducing agent. It is used to reduce oxides of metals like Cr, Mn, Fe in the Thermite process.

The thermite reaction produces enormous heat (∼3000°C), enough to weld railway tracks and extract metals like chromium and manganese.

Step 4: Refining of Metals

The metal obtained after reduction is impure. It is refined to obtain high-purity metal. The most common method is electrolytic refining.

🔋 Electrolytic Refining

🔄 Complete Extraction Flowchart

📊 Extraction Method Based on Reactivity Series

🔧 Corrosion — Rusting, Tarnishing & Prevention

Corrosion is the gradual destruction of metals by chemical or electrochemical reaction with their environment. It is a natural process that converts refined metals into more stable compounds (oxides, hydroxides, sulphides).

🟤 Rusting of Iron

Conditions required for rusting: Iron rusts only when both oxygen (air) AND water are present.

🔬 Activity to Show Conditions for Rusting

Take three test tubes with iron nails:

• Test tube A: Nail + water (air excluded by oil layer) → No rust (air needed!)
• Test tube B: Nail + dry air (with anhydrous CaCl₂) → No rust (water needed!)
• Test tube C: Nail + both water and air → Rust forms!

⚪ Tarnishing of Other Metals

🛡️ Prevention of Corrosion

Corrosion causes massive economic losses. Several methods are used to prevent it:

1️⃣ Galvanization

• Zinc is more reactive than iron, so it corrodes preferentially (sacrificial protection).
• Even if the zinc coating is scratched, the zinc corrodes first, protecting the iron underneath.
• Used for: iron buckets, pipes, roofs, automobile parts.

2️⃣ Electroplating

Coating a metal with a thin layer of another metal (Cr, Ni, Cu, Ag, Au) using electrolysis.

• Chrome plating: Car bumpers, taps, kitchen appliances — shiny and rust-resistant.
• Silver/Gold plating: Decorative items, jewellery.
• Tin plating: Food cans (tin is non-toxic and corrosion-resistant).

3️⃣ Alloying

Mixing metals with other elements to form alloys that resist corrosion.

• Stainless steel: Fe + Cr + Ni — does not rust. Chromium forms a protective oxide layer.
• Brass: Cu + Zn — more corrosion-resistant than pure copper.
• Bronze: Cu + Sn — ancient alloy, highly durable.

4️⃣ Paint, Oil & Grease

Applying a protective layer that prevents contact with air and moisture.

• Paint: Used on iron gates, bridges, ships.
• Oil/Grease: Used on machine parts, tools.
• Plastic coating: Used on handles, garden furniture.

5️⃣ Sacrificial Protection

Attaching a more reactive metal (Mg, Zn) to the structure to be protected. The more reactive metal corrodes first, saving the structure.

• Used for: underground pipelines, ship hulls, water tanks.
• Magnesium blocks are attached to the hulls of ships to prevent corrosion of the steel hull.

📊 Corrosion Prevention Methods Summary

📝 Practice Questions (With Answers)

1. Q1: An element A reacts with oxygen to form compound B which has high melting point. This compound is soluble in water and turns red litmus blue. Identify element A and compound B. Write the balanced equation and state the nature of B.
2. Q2: Why is sodium metal stored under kerosene? What happens when a small piece of sodium is dropped into water? Write the balanced chemical equation.
3. Q3: Explain the extraction of iron from its ore. Describe the role of carbon monoxide in the blast furnace and write the chemical equation involved.
4. Q4: What is galvanization? Why is zinc used for galvanizing iron even though it is more reactive than iron? Explain the principle behind this method.
5. Q5: A metal M does not react with dilute HCl but reacts with oxygen to form a black compound. When this black compound is heated with hydrogen gas, it forms reddish-brown M again. Identify M and write all chemical equations.
6. Q6: Arrange the following metals in decreasing order of reactivity: Zn, Cu, Na, Fe, Ag, Al, Ca. Which of these metals would react with cold water? Which would not react with dilute HCl?

✅ Answer Key

• A1: A = Mg (Magnesium), B = MgO (Magnesium oxide).
  2Mg + O₂ → 2MgO. MgO is basic in nature — turns red litmus blue.
  MgO + H₂O → Mg(OH)₂ (magnesium hydroxide — a base).
• A2: Sodium is stored under kerosene to prevent contact with air (O₂) and moisture (H₂O) as it reacts explosively with both.
  2Na + 2H₂O → 2NaOH + H₂↑
  Sodium catches fire spontaneously on water — the reaction is highly exothermic.
• A3: Iron is extracted from haematite (Fe₂O₃) in a blast furnace using coke (C) and limestone (CaCO₃). Coke burns to form CO, which reduces Fe₂O₃ to Fe:
  Fe₂O₃ + 3CO → 2Fe + 3CO₂↑
  Limestone removes impurities as slag (CaSiO₃).
• A4: Galvanization is coating iron/steel with a layer of zinc. Zinc is more reactive than iron, so it corrodes preferentially (sacrificial protection). Even if scratched, zinc corrodes first, protecting the iron underneath. This works because Zn is above Fe in the reactivity series.
• A5: M = Cu (Copper).
  2Cu + O₂ → 2CuO (black copper oxide)
  CuO + H₂ → Cu + H₂O (hydrogen reduces CuO to reddish-brown Cu)
  Cu does not react with dilute HCl because it is below hydrogen in the reactivity series.
• A6: Na → Ca → Al → Zn → Fe → Cu → Ag (decreasing order).
  Na and Ca react with cold water. Ag and Cu do not react with dilute HCl.

📋 Previous Year Questions (2017–2026)